I too wouldn't hesitate to fire one like that, if it were on face and the barrels hadn't been reamed too thin by somebody removing pits. Black powder loads (paper, or brass, or plastic hulls for a one time firing, or BP equivalent smokeless loads concocted with PB powder or the like).
Do the barrels "ring true"? That's to say dismount the barrels and suspend them by the hinge and tap them with a small hammer- they should chime like a bell. If they don't that means one or both ribs has an issue such as solder joints coming undone, or worse lots of rust under the ribs which might be eating into the barrels.
The one thing in the pics that give me a little pause is the extent to which the firing pin holes in the standing breech are hogged out. Expect primers to flow back into those huge gaps and potentially locking the gun shut after firing. Lots of room there also for errant gases to flash back through in the event of a pierced primer. Wear glasses!
Last edited by gnoahhh; 03/19/19.