I have personally not seen one, but as I previously mentioned, early in the war the Brits were buying up whatever revolvers they could find, even sometimes from US retailers and distributors. In some cases, they would buy commercial M&Ps chambered in .38 Special, then just run a .38 S&W reamer into the chambers. Very simple. You may very well have one of those rechambered commercial .38 Special M&Ps bought in the US by the British Purchasing Commission in 1940.