Here are my prewar K frame targets, although I don't know if the .22 Outdoorsman counts as an M&P. From top to bottom:
.38 S&W Special, serial 317879
.32-20, serial 128847
.22 LR, serial 674189
I've lettered only the .22. It shipped on May 2, 1939 to Kelly-How-Thompson Co. of Duluth, MN. It has a lanyard ring that was ordered by the distributor on Oct 8, 1940 and was probably installed by them. It's also been refinished, probably not by the factory either.
Now that I look at the pictures (which were taken in 2016), I realize that I no longer have the .38. It had one of those miserable little U-notch rear sights and thin front blade, so I bought a different M&P Target (serial 666024) with a proper square notch and Patridge front sight, like the .32-20 has. Plus it was in nicer condition.