[Old and Reliable]

My guess is- if it was done with files, had to take some time. Sears and their mating contacts with the hammers- today 6150 Chrome Vanadium steels- RC 52-56 possibly. Not sure what grade steel Parker used, or heat treating range either

If this "work??" was done with a grinder, even with a quench and grind process, resultant heat input can pull hardness from the sear,- NOT a good thing. Also looks like the re-bored axle hole is out of round and with a drill bit with differing shoulder angles on the flutes, as evidence by the surface meatl "sprue" that was not ground off flush to the surface.

For whatever reasons this sear was altered, pretty sloppy bit of work- IMO!!