I recently acquired my first M1 Carbine. It's a National Postal Meter receiver in the first batch of serial numbers, which I've gathered puts it between February and September of '43. Underwood 6-43 dated barrel, Winchester trigger group with a push button safety, first type modified mag catch, and Inland Type III bolt. It's got a rebuild mark from STD Products. And it's NOT import marked :)
Here's a couple photos I took while I was inspecting it. I'll get some better ones up soon when I get my camera back
https://www.milsurps.com/images/impo...184DE491-1.jpg
https://www.milsurps.com/images/impo...3F8F8061-1.jpg
https://www.milsurps.com/images/impo...87E98B71-1.jpg
https://www.milsurps.com/images/impo...2BC45181-1.jpg
https://www.milsurps.com/images/impo...B3B16521-1.jpg
Looks like some arsenal patch jobs on the stock too maybe
https://www.milsurps.com/images/impo...0CAAEF21-1.jpg