Now let's see what exists to justify these claims:
Zoroaster was born of a virgin and "immaculate conception by a ray of divine reason." It's hard to quantify this one -- the Avesta (note again, a late source, later than Christianity) refers to a "kingly glory" that was handed onward from one ruler to the next; this glory resided in Zoroaster's mother for about 15 years, including during the time she was married to Zoroaster's dad, Pourushaspa. It seems that a human father was still needed for Zoroaster [Jack.ZP, 18, 24] and that this "ray" was merely for the infusion of Zoroaster's spirit, not his body.
He was baptized in a river. I can find no reference to this at all. There is a story of Zoraster receiving a revelation from an archangel while on the banks of a river, which Zoroaster later crosses [Jack.ZP, 41], but that is as close as I have found.
In his youth he astounded wise men with his wisdom. Here's what I have on this: At age 7, Zoroaster was placed under the care of a wise man; as he was raised he had disputations with the magi -- the practitioners of occult and magic, necromancy, and sorcery. These were "put to confusion" by him [Jack.ZP, 29, 31]. Later he also made sport of the wise men of King Vishtapsa, who became one of his major converts [Jack.ZP, 61-2], and these wise men plotted against him, accusing him of being a necromancer. Zoroaster was imprisoned, but got out when he helped heal the king's favorite horse by making its legs grow back. Zoroaster was clearly a prodigy, but in quite a different area than Jesus.
He was tempted in the wilderness by the devil. This one is true, sort of -- after 10 years (not 40 days!) of visionary experiences, a sub-demon named J. Buiti was sent by Ahriman (the functional devil-equivalent in this context -- he didn't come himself) "to deceive and overthrow the holy messenger." [Jack.ZP, 51]
This temptation involved an attempt to persuade Zoroaster to renounce the "good religion" of Mazdeism and worship evil spirits -- no bread to stones, no leaps from towers, but it bears at best a superficial similarity to the temptation of Jesus.
He began his ministry at age 30. This one is absolutely right [Jack.ZP, 16], but rendered meaningless in this context by two things. First, it comes from the Pahlavi literature, which is post-Christian by several centuries, and second, thirty is the age at which Iranian men come to Wisdom. [WL, 54] The ancients gave as much regard to the "big three-oh" as we did -- there is no copycatting here.
Zoroaster baptized with water, fire, and "holy wind." This is kind of odd, because this would equate with a "John the Baptist myth," not a Christ myth! Even so, I find no evidence of any of these at all. Zoroaster did have an association with sacred fires [Jack.ZP, 98] that were part of the fire-cults in three particular temples, and seemed to have taken a part in preserving the fire-cult (which liked to keep the fires going, sort of like our eternal flame at Arlington Cemetery) but he did not "baptize" with and of these things.
He cast out demons and restored the sight to a blind man. "Cast out" is a little vague for a description here -- Zoro apparently didn't like demons, but I find no record saying he cast them out of people as Jesus did: This was one of several abilities Zoro had, including driving out pestilence, witches, and sorcerers. There is a record of Zoroaster healing a blind man, but this comes from a document dated to the tenth century AD -- and he did it by dropping juice from a plant into the blind man's eyes. [Jack.ZP, 94]
He taught about heaven and hell, and revealed mysteries, including resurrection, judgment, salvation and the apocalypse. As this goes, it is true, but not all of these terms have the same meaning in Zoroastrianism that they do in the Judeo-Christian tradition. Only "resurrection" is a good match here -- Zoroaster's faith taught that after judgment, the "dead will rise up" and men will become "not-aging, not-dying, not-decaying, not-rotting" [Herz.ZW, 299]. It's resurrection, it sounds like, though described by negatives.
In terms of the other stuff, there aren't a lot of similarities [Wat.Z, 95, 96, 98, 102]. Salvation was by works alone; there was "practically no place for repentance or pardon:" and "no doctrine of atonement." There is some issue about the fate of the wicked; one account says they will be tormented three days, then return to do good deeds; another source says they will be annihilated. There is an essential equivalent to Heaven and Hell, but it wouldn't be too hard to create such a concept independently one way or the other based on the simple assumption that people will get what they deserve.
Judgment would be made by committee: the Persian Mithra and two other gods are on the panel. If you aren't sure where you might go, word is that Zoroaster himself will come and plead for you. A concept of purgatory appears in a Zoroastrian work of the 5th-6th century, and later Zoroastrianism did develop rites of repentance and expiation, contrary to Zoroaster's recorded teachings. There's an apocalypse planned to be sure: a flood of molten metal to burn off the wicked. Zoroastrian eschatology comes for the most part, however, from those late AD sources [Yam.PB, 465].
A reader also sent us this note:
"The case for a judeo-christian dependence on Zoroastrianism in its purely eschatological thinking is quite different. And not at all convincing, for apart from a few hints in the Gathas which we shall shortly be considering and a short passage in Yasht 19.80-90 in which a deathless existence in body and soul at the end of time is affirmed, we have no evidence as to what eschatological ideas the Zoroastrians had in the last four centuries before Christ. The eschatologies of the Pahlavi books, though agreeing in their broad outlines, differ very considerably in detail and emphasis; they do not correspond at all closely to the eschatological writings of the intertestimentary period nor to those of St. Paul and the apocalypse of St. John. They do, however, agree that there will be a general resurrection of the body as well as soul, but this idea would be the natural corollary to the survival of the soul as a moral entity, once that had been accepted, since both Jew and Zoroastrian regarded soul and body as being two aspects, ultimately inseperable, of the one human personality." -- R.C. Zaehner, The Dawn and Twilight of Zoroastrianism. G.P. Putnam's Sons. New York. 1961. Pg. 57
Note especially the implication that an idea of resurrection could have come up independently in the Zoroastrians because they shared the Jewish perception of totality of body and spirit.
He had a sacred cup or grail. If he did, the Zoroastrian scholars don't know about it. Not that it matters -- the idea of Jesus having a sacred cup or grail is a product of medieval legend, not the Bible!
He was slain. Zoroaster was indeed said to be slain, but his death isn't vested with any significance. There are a couple of stories about his death. A late story has him struck by lightning, but that is from a post-Christian source. An account that is generally accepted has Zoroaster killed at age 77 by a wizard/priest. There are no details on this death, other than that it occurred in a temple. A nice story from the 17th century has Zoroaster whipping out rosary beads and throwing them at his assassin as he dies. [Jack.ZP, 124-9]
Either way, Zoroaster's murder has neither the invested significance nor the surrounding similarities of the death of Jesus. There is also a third account that has him killed in battle as a king! However, none of this may matter as Herzfeld, after analysis of the data, concludes that the "murder of Zoroaster is entirely unhistorical" for the stories of it are all in late sources as much as 1400 years after his time, and had he truly been murdered, it would "resound loudly and persistently in history" before that [Herz.ZW, 241, 845].
His religion had a eucharist. Not that the Zoroastrian scholars are aware of, though I would not doubt that the Z people had communal meals like every religious and political group in ancient times. And since there is no atonement in Zoroastrianism, how can there be a Eucharist? The closest I can find to this is the fact that in later Zoroastriaism, there is a rite involving the intoxicating haoma plant, which may or may not have been known of and/or endorsed by Zoroaster [Yam.PB, 418] and involves a daily rite of consumption with no "eucharistic" significance (i.e., it is not Zoroaster's body or blood, etc.).
There is also a ceremony calls the yasna or veneration, which does involve the use of bread (topped with clarified butter) and a drink made from ephedra, pomegranate twigs, and milk (strained through a filter made from the hairs of a white bull), but evidence indicates that this ritual was established as part of liturgical reform in Zoroastrianism in the post-Christian era [Yam.PB, 449-50].
He was the "Word made flesh." Not that the scholars know about it, either.
Zoroaster's followers expect a "second coming" in the virgin-born Saoshyant or Savior, who is to come in 2341 CE and begin his ministry at age 30, ushering in a golden age. I have been able to confirm that this is true to some extent: a return is expected in 2341 CE, to start a golden age; the details on age 30 I have found nowhere. Whether this future Deliverer would indeed be Zoroaster himself again is indeed something that has been interpreted, but later Zoroastrian texts think that the person will be of the line of Zoroaster, not Zoroaster himself. [Wat.Z, 94-5]
Zoroaster vs Jesus
I think you can see how this kind of discussion can snow ball. You chose well. Persia is the best candidate for outside Biblical influence but on closer inspection many of the claims evaporate. Anyway this is a start I guess.