Have you tried Ebay? I can't remember the name of the seller, but there is a person who sells a lot of old replica revolvers.....not sure if this is one of them though.
I have one of those that is supposed to fire blank caps. A friend who looked at it said it was made by MGC, but all I see is japan stamped on it. It does seem to have some residue in the cylinder from some kind of firing, but real lead balls will not go in it due to plugs. I got it at an antique store a few years back. There is no engraving anywhere on it, and the frame is steel, not brass.