I've had two other Model 39's. The first one was a 39-2, an old police sidearm judging by the wear, but at the time I wasn't interested so sold it to a friend.
The second one was a Model 39, that developed hammer drop when shooting, I didn't feel like messing with it so sold it to a collector.
When I decided that I wanted another, or actually a 9mm that I liked, I wanted one with an ambi-safety. After looking at some 39's it dawned on me to look for a 439, and that is this one:
That is a nice example. Never had a 439, but had 539s, 639s and 3906s. All with the adjustable sights like yours. I liked the adjustable sight protected by the "wings", and that the 2nd. and 3rd. Gen guns have the firing pin safety.