Thanks all!
The source of this coin is completely different from the Liberty
Seated dollars.
When I found out that there were not minted any 1862-O seated liberties, the other one would obviously also be a fake one.
This one however, is from a local coin dealer. So I don't know/think this one is fake, although everyone can make mistakes.
Glad I didn't buy any of them just because they looked "alright" :)