Generally I don't do value estimates, I doubt anyone would be prepared to estimate value without at least some good quality photos. I can suggest a couple of pros and cons.
1. Based on your information it appears there is no collector value. Military collectors want unaltered examples, and in any case U.S. collectors naturally tend to be more interested in revolvers made for and used by U.S. armed forces.
2. M&P revolvers prior to s/n V769000 (about December 1944) had an older style spring-powered hammer block which could on occasion stick and not function as intended. A new more positive hammer block was designed at the request of the U.S. Navy after a sailor was killed when a revolver was dropped onto a steel deck. With the older hammer block I'd only carry with an empty chamber under the hammer.
3. Although it's been done thousands of times I personally wouldn't shoot .38 Specials in one of these converted .38 S&Ws.
1. It is an S&W and it is not junk. At the time it was made it was equal in quality and finish to S&W commercial production. Even those made in later years under wartime pressure were every bit as good in terms of steel quality, heat treatment, parts fit and operation, just without the fine polish and blue finish.
2. Checkered grips with the diamond pattern around the grip screw would be correct for the time this was made. They may well be the original grips and as such would have collector value in themselves.
3. You say the barrel length is 2 3/8", which means it likely retains the front lug into which the ejector rod latches. Those shortened to 2" lost the lug in the process, meaning the cylinder locked only at the back. Assuming I bought a converted model at all, I'd much rather have one with the front lockup intact.
4. You say the crown and front sight appear to be factory. Again assuming this is a conversion, this suggests the job was well done.
Without photos I doubt anyone would want to hazard an estimate; even with photos an estimate would only be over a fairly broad range. I will say if I saw it for sale at a gunshop, it would be the grips I'd be most interested in.
Also just one further point, M&P revolvers made for Britain were mostly with 5" barrels, though 4" and 6" barrels are known as well. Roy Jinks says the Victory models made in .38 Special for U.S. sales were mostly made with 4" barrels but some made with 2" barrels and the appropriate-length ejector. I've never seen one, even in photos, but I've read there are some examples owned by collectors.