Impossible to answer without the sn.
@ late 70s
AROUND 1986
sometime in the early 60s
Roughly mid 1960s.
@ 40 yrs old
You need to visit a reputable gun shop for this answer!
100-400 as described.
Late 60's to early 70's
early 60s or so
early 60s or so
No English sn data published