The closer lock Not the fancy effort might serve if you weld up the drum hole and shorten the front part even if a spring is needed if the one in it is too long even if the hammer dosn't quite suit there are other hammers should . .Just my view but ide say you where close .
could be a gun put together from cannibalized parts. One thing I can tell you. The ONLY gunmaker I have ever seen use a cheek piece that starts at the wrist like that was Peter Angstaft of Berks County PA near Kutztown. That feature is quite peculiar. The rest of the gun is any body's guess. Angstadt did use ready made locks. being so close to Philadelphia and a gun making area. I had the pleasure of seeing one of his rifles up close a few years back. The one I saw came from the large Kindig collection. Angstadt's brother, Jacob, was one of my ancestors. BTW, there were three Peter Angstadt gun makers. Some people get them mixed up as one person.. each was different. IIRC the gun I saw was made by either Peter 2 or Peter 3.