Thanks for the input, the Standard Catalog is supposed to be the definitive source.
From more reading, mine is more likely from the 1946 run which was basically a scrounging and garbage disposal operation by S&W. The frame at the crane recess has the eagle and "S2" stamp, indicating WWI leftover, and the serial number is the lowest I've seen so far on a Brazilian contract revolver though I did see a 148xxx for sale. The SW forum had a good explanation of the random serial number WWI surplus frames popping up, there's no real record of the entire list that were exported, just a few definite ranges with a sprinkling of "floor sweepings" to make up the last bit.
This revolver already has an Aristocrat sight rail and ginormous bull barrel, but I don't shoot silywet and besides, I have a model 19 configured that way already. I'd like to make this one a shooter again since the barrel is bulged and loose in the frame, the crane hole is very wallowed where the cylinder pin passes through, and the added crane detent balls are a disaster.
I might set the barrel back and turn it down to a reasonable profile, weld on a boss for the base pin, replace the pin tip with a "doll head" from Numrich, and sort out some kind of front sight. Still mot sure if the frame is u-notched or flat topped with square groove, but it appears to have a 1917 frame so it shiuld be round. For $250 I could get a parkerized 5.5" NOS barrel, blue and fit it, replace the doll head, fix the other problems, and make it original-ish but I have no interest in spending that kind of money on a beater.