Hey sorry for taking so long,
the issue has been resolved now. They changed the mail address to the original one and asked for a password reset. We managed to get in contact with the customers that bought the accounts. They used alts.top. I guess this website fishes for old accounts that they think may be forgotten and nobody will realize have been stolen. I've reported it to Mojang though.
Oh, and as for the question itself (hehe): I paid with PayPal if my memory doesn't fail. Hope you get it back soon!
