I have an old, well-work Parker hammer double. Old "hardware store" grade gun. 12-gauge, 30" Damascus barrels. Still locks up as tightly as the day it was made. One hammer screw is missing about 25% of it's head.
Years ago the late Oscar Gaddy did some minor repair work on this gun for me. With him gone, I'm not sure who to turn to.
I expect that Brownell's will have screws that will work, but I would prefer to get an old one if someone still has them. A shiney new blue screw is going to stick out on this gun like lipstick on a pig (no offense to my fine old Parker)
TIA
Tom