YOUR 39A WAS MFG. IN 1963
1957-1958
1963. sales@countrygunsmith.net
1967
Manufactured 1964
1960
Your serial number indicates that your Marlin Golden model 39A was made in the year 1974.
Based off of the sn you posted 1966. http://armscollectors.com/sn/marlinlookup.php
YOUR 39A WAS MFG. IN 1949
The S prefix to your serial number indicates that your Marlin model 39A was made in 1958-1959.
By the serial no and if it's a golden it's a 39A not a 39. either a letter prefix or a leading 2 digit no will tell.
1960