This percussion lock came to me in a box of random parts and I've tried unsuccessfully to identify it by looking at "mugshots" of L&R, Dixie, and Pedersoli locks.
The distinctive features, at least to my eye, are the bridle cutouts, the adjustment screw (red arrow), and the curve of the lockplate (also marked in red).
My guess is that it's Italian or Spanish, but thought somebody on the forum here would recognize it. Thanks, SCL