You have a modified WWII British Service Revolver (BSR) aka a pre-Victory, which was shipped around mid-1941. S&W made close to a million of them from 1940 to 1945, the majority of which went to the British Commonwealth for military use. Up front, it has no collector nor significant monetary value. When the British surplussed these out in the 1950s-60s (in their original condition), many American surplus gun importers bought BSRs for scrap iron prices, and had them rechambered from .38 S&W to .38 Special, chopped the barrels shorter (most originals had 5" barrels), often refinished them, and added some cheap plastic grips. Yours fits that description all the way. Boatloads (not an exaggeration) were given the same treatment. They sold by mail order for around $25 at the time, and adjusted for inflation, are still worth about that today, if not less, as they are nowhere near being in their original condition. Good mainly as a truck gun or a throwaway. But they will shoot if needed. Allegedly Lee Harvey Oswald used one much like yours to kill Officer J. D. Tippitt of the Dallas Police after the JFK assassination.