looks ike a really early as in 1960s or 70s bubba brownbess 3rd model, trigger looks like its off a french M1842, lock looks typical of the early repros as dose the fitting to the stock, look how out of place the lock is where its inlet, and who ever it was put the front swivel in the wrong place. if it sparks and the barrals thick anough at the breech I'd say 400$ max.