K-38 Combat Masterpiece is the way to go. From what I could see it looks like a 4 screw.
Well you would have to see the other side to know. The 5th screw is the upper side plate screw on the RIGHT side in front of the hammer. When I referred to it as a 4 screw, I meant at least a 4 screw. You can see the trigger guard screw but that doesn't make it not a 5 screw either. That screw is there on any 4 screw OR 5 screw gun. Is there another way you can tell? You could also tell by SN by I don't see the SN listed anywhere.
Here are some K-38 variants I have.
Here is the daddy to the K-38, the M&P 38 target. This one is a 1905 4th change and dates to approx the early 1930s. SN 63XXXX.
In this photo, there are 2 M&P 1905 1st change guns, top and middle. They date to the teens. The one has "1914" and some other notes which I believe to be a name and address of a previous owner on the grip panels. Both guns have their original K frame concave grips which are hard to find today. The bottom gun is a 5 screw K-38, K111XXX IIRC. Unfortunately some genius removed teh case hardening from the hammer and trigger. It has the standard diamond magna grips (target grips were optional) and a fish hook aka speed hammer, also standard in that era.