Eric, the narrative on old smooth rifle 3506 tells us the "Tapered & beveled engraved lock has well sculpted goose neck serpentine cock", so the current piece must be special and more valuable? Show us what you would replace it with? That seems to me an odd shaped lockplate - unlike most other rifles of the area, and could sure look better with a few new components. The C's Spring gunshop did turn out an occasional "self made" lock. But they also had locks valued from a few shillings to 2 Pounds plus, so cheap locks to go along with the good and fine.
TCA, 3520 is first "elegant and fine, made in Kentucky" in the title, then a Swiss or European copy of a American rifle in the narrative. It looks totally European to me, but maybe the writer thinks it's a copy of our colonial rifles because of the long barrel? It has a military or militia look, except for the carving in a few places - what do others think? I don't think they were copying our longrifles over there - rather we were turning German and Swiss rifles into PA style here. There's a Hauschka rifle with long barrel in The Lancaster Rifle, and a few others pictured here and there. This would make a good separate thread. Bob