I have an Underwood with all matching parts, barrel is dated 12-42 and the serial numbers put the production date around March of 43. I purchased it back in the late 80's. It's the most fun you can have with your pants on. I love shooting with it at the range, have used it on a pig or two and a few coyots have had a bad day as a result of ability to shoot qickly. Yours is a fine M1 own it with pride.