Jake, I am going to have to recant on the harness buckle. The name misspellings (Shur-Lok Vs Sure-Lock) didn't come into vogue until the mid 1900's. Unless it came from a newer harness, I will have to change my stab in the dark to a purse buckle or something similar.
you just gave me an idea with the purse!! you know those clasps where its like a buckle or hinge and two balls lock together holding it shut? like this?