There's some history of faking up the colt pocket models. The usual alterationis faking up the square backed trigger guard as they were rarer than the round ones. It also sometimes happens that that italian replicas show up here with no proof markings or manufacturers marks. People deny this and make up all sorts of weird scenarios to explain them away but it does happen.
I don't know if you are talking about a colt or some other percussion revolver but if you see a manufacturer's address line on the barrel, its either an original or somebody went to a great deal of trouble to make it look like one.
