Good score! Interesting front sight. Was it a Patridge that got modified or a Baughman that got modified?
I think with the 19-3 and -4 you could get either one depending on trigger and hammer. I have a -5 and by that time the red ramp / white outline sights were standard along with the target hammer and trigger.
What I meant by that is which sight was modified into the one this revolver has? t looks in between the two; has a red insert but the sight itself looks almost like a Patridge blade and the Patridge did not have a red insert.