I've talked with several people that had the screws repaired or replaced on several Parkers by Turnbull mfg. and were quite happy with the results and the cost in doing so was quite reasonable. I've also seen several of their screw repair jobs and was amazed as to how they were engraved and color blended to match the surrounding patina. I ran a finger across each screw and swore it felt original to the gun. This would probably be your surest bet and you'll be quite pleased. G