Your Browning light weight 20ga.auto-5 shotgun was made in the year 1964,with the serial number that you have provided.
Only the "light" Twenty" had a gold trigger. My 1964 Belgium Browning Light Twenty has a gold trigger.
100-1000 USD or more depending on specifics.
The PZ found in the middle of your serial number indicated that your browning light twenty auto-5 shotgun was made by browning in 1981.
Need a detailed description.
1973
Browning's web site has a sn search function.
50-375 usd
1966 light twenty auto5man
50-500 USD or so
this is a 1969 light twenty shotgun auto5man
this is a light twenty made in 1965 auto5man
Go to Browning's web site. They have a sn function listed under customer service.