I only have a quick reference quick for the S&W company so it doesn't give detail the same as Roy Jenk's book but it a dateline for the modern autoloading pistols (39,41,44,48,52) of 1854 - 1970 with serial number range 1001 - 11500. So I'm guessing yours would be the late 1960s.
Perhaps someone else can chine in with more accurate data.