I've never seen one like that. Murphydog brings up a good point about the crispness of the edges and stampings but to looks a bit too uniform and not quite the color I've normally seen. I'll go with a treatment of some kind but I could certainly be wrong.

In any event it looks fine and I'm sure it shoots great. You said it's your favorite carry gun so enjoy it as it is regardless of it's history. You will find many fans of the 39 around here myself included although all of mine are 39-2's. I'm still looking for my first 39 no dash.

Welcome to the forum!