Believe it or not, on my first brief session with this gun, I didn't take a photo of the barrel date, but believe it was 11-42 and had the flaming bomb. Also have to check the trigger guard and all else. Was looking at the extractor and did not see any R on the side. It may be hiding though. Next session I am bring the good camera with excellent close up skills. Besides the stamping, is there anything else that makes you think it is an A3 stock?