[rhmc24]

The 'cobbled together' clincher for me or major modification is the screw forward of the trigger guard, without exception (my experience. that period) the front attachment should be with a tab up into the stock, held by a cross pin & to a lesser extent, the aft screws. Muzzle treatment likewise questionable.

Offsetting that is the apparent skill and workmanship, particularly the grip treatment, all possibly explainable as an original French style pistol with barrel shortened and trigger guard replacement. I can't see enough of the lock inlet to have an opinion.

All of which is beside the point about the lock pan cover 'anomaly'.

I agree the pursuit of useful info about its history is likely an excercise in futility.