Found a thin stamp 1st Edition Base Rattata, as far as I know these are pretty rare. How rare are thin stamp 1st Edition Base Non Holos, does anyone have a guess on price? It is raw but I would say it could grade a PSA 8. I am aware this would probably be a very niche piece, and prices could widely vary.
Anytime these come up for discussion, I always reference @quuador article (linked below). The article touches a small bit on it and it seems that they are extremely rare. To your point, they are very niche and therefore would be tough to estimate a price. Not sure how many people are actually aware of such variant and are actively looking for them.
Actually, the non-holo thin stamp Base Set cards are usually not as thin as actual Thin 1st edition stamps we see on holofoil Base Set cards, other WotC era sets, or other languages. The width of the “1” is kinda in between an actual Thin and Thick stamp. Here an example of all three stamps (in the order non-holo thin Base Set; actual Thin stamp; Thick stamp from left to right - the non-holo thin Base Set stamp is graded, otherwise I would have put them in increasing order…):
So they didn’t accidently used the Thin stamps for some non-holo Common/Uncommon sheets, but instead it’s just a printing error like grey stamps, back imprinted stamps, etc.
Some of the non-holo thin stamps I’ve seen were also partially smudged with black ink, further explaining why it got a thin stamp. Like this Red Cheeks Pikachu at the top for example (not mine ):