I just bought a 38 M&P in January of this year. Serial # 138xxx that was made in Dec. 1950. It came with the gold box and cleaning rod and looks like it was hardly used. It has a 6" barrel and all the numbers match including the box.

I paid $550, which I thought was about $50-75 too high, but they were firm on the price and I personally don't see many M&Ps in that good of shape from that time period, so it came home with me.