Wellll....they started making those neat imitation "Mk V"s around 1971, if I remember right. That's a fairly low serial number so I'd say maybe the late 70s or here abouts, roughly.
I got mine in mid '71. One of the first, SN 006XX, it came with a 22" medium weight barrel but they quickly changed to a 24" lighter barrel. They seemed to sell pretty fast in those days. It's been a good 'un too, lots of dead crows and ground hogs plus a goodly pile of whitetail to it's credit.
