There are a lot of bit and spur guys in Texas that have done a few guns. I think I have seen that mark on a bit in the past on the bit ans spur makers forum. Fred
I know nothing of engraver's marks, but there is info out there on gunmaker's marks, and jewelry hallmarks. Although not a lot of engravers out there, unless you maybe look at the world's population, I wonder if anyone has thrown together a booklet of some sort with all the known engraver's marks/initials? I used to belong to the AWI, and they assign you a unique mark that they keep on record. I always wondered about that sort of thing.