Hmm. By the SN, that gun is a medium grade, made sometime between 1936-43. Sometimes the date stamps are very clear, sometimes not so much. As best I can see this one, and given the SN, I'd say it's a 1941 gun. But you can find out a whole lot more by contacting Bob Beach at Griffin & Howe. He'll have it in their books if it's an A&F import.