You make several Christian-based assumptions.
What are they? I'm curious & would like to know what you're referring to.
I'm neither Christian, nor do I belong to an Abrahamic religion.
Same with me & I also don't belong to any religion, in general.
But I digress. What is analogous to a stamp (you've willingly and perhaps unwittingly already listed a few) would be places of worship, religious texts, religious idols, manifestations of divinity, and personal experiences.
With what I was referring to, the places of worship, religious texts, and religious idols are not analogous to a stamp. The stamp is the thing to be proven as something that exists analogous to deities & afterlife.
Place of worship are no different from any other building constructed out of wood, brick, mortar, steel, etc. The existence of places of worship don't prove anything about the existence of deities or afterlife anymore than a convenience store, a widget factory, a hospital, or an outhouse does.
Religious texts are no different from works of fiction, instruction manuals, and recipes in that they're authored or written by human beings and published in hardcopy form on printing presses that were designed and constructed by human beings.
Same goes with religious idols; for example, the same type of wooden or ceramic materials used to construct them are also used to make chairs and soup bowls.
None of these man-made things or items are proof of the existence of deities or an afterlife; they are only things associated with a belief in the existence of such concepts.
What are perceived as manifestations of divinity can and have been explained as hoaxes, illusions, con artist deception, or scientifically explainable phenomenon that the perceiver didn't understand. Same applies to personal experiences that are believed to be the result of the existence of deities or an afterlife.
Notice that I'm not claiming that deities and an afterlife do not exist; I'm only referring to the belief in them & lack of proof of their existence in such a way that meets scientific scrutiny, as in being demonstrable, experimentally repeatable, measurable, etc.