Cool Pre Model 24.
The "wonky" sight of course was modified from a long barrel's Patridge sight and the base is miss-shapen from amateur polishing, then cold blued. That has to go. It needs a replacement proper Baughman ramp sight.
The narrower rib is indicative of it's early vintage and not unlike the first rib used on the 44 Target Post War Transitional Models. A neat early feature.
The roll marking on barrels varies in placement even on same barrel lengths, but its barrel marking location has that going for it. The changed sight goes against it.
Might just as well wait for the letter. So I need not speculate.
You'll get opinions enough on the 4" originality. Suffice to say you got a great 44 shooter and maybe collector.
Other threads discussing 4" barrel marking and verifying originalness:
.44 Special ctg?!?
Was this Barrel Cut? 1950 Target
44 pre-24 Four Inch