Years ago there was a guy that posted ATS, and possibly here, that would offer to plug holes in damaged coins. Full disclosure, no attempted deception. He did it just so someone could have a better looking example for their collection. I saw some of his work, and it wasn't half bad. I don't remember his name, and I don't know if he's still around, but I will give you the names of a few long time members, and maybe someone can tag or PM them and see if anyone who remembers him will respond. (Sorry. I don't know how to tag people on here.)
MarkFeld, gmarguli, Messydesk, AlexinPA
I think Rodger Burdette and James Garcia were both posting ATS back then, too.