I built an Investa Arms flintlock .50 caliber Hawkens from Cabella about ten years ago. The inletting was OK except for the patch box which had about a 1/8 inch gap. I spread the brass by working it with a small hammer to fill the gap. I didn't like the geometry of the lock, the flint was hitting on the lower 1/4 of the frizzen and putting a longer flint in didn't seem to help. I ended up getting a Siler small rifle frizzen and moved the pivot point by about 1/8 of an inch which made the lock work a whole lot better. The Siler frizzen also has a slightly different angle on it's face. The Siler frizzen seemed to heat treat better than the one from Investa Arms and gives a real nice spark with the proper flint. Still have the rifle and like to shoot it when possible.
Real nice looking flinter you have there, just keep the flint, frizzen and pan clean and dry and she'll shoot fine.