The letters AA identify the year of manufacture of your Marlin 39A golden Mountie as 1965.
The prefix letter W to your serial number identify,s the year of manufacture as 1963.
1960
A serial number would be required to identify the year of manufacture of your Marlin model 60.
1965.
Year of manufacture for a Marlin 880 SQ, 1996
The 20 indicates that your gun was made in 1980. Marlin did not checker the stocks on the 39a at that time period.
The year of manufacture for U2893 = 1960 (August)-1961. http://armscollectors.com/sn/marlinlookup.php
1947
With the serial number that you provided,your Marlin model golden 39A was produced in the year 1964.
The VIN number will identify the year of manufacture.
Your serial number indicates that your Marlin golden 39A was made in the year 1982.