You can get gun pricing at http://www.UsedPrice.com. They are a good place to start.
50-550 usd
50-600 usd
Stalker
1926; 50-500 usd
You will have to call Browning for an answer.
Check the receiver and barrel.
50-575 usd
The letters PY that are in the middle of your serial number,indicate that your Browning Auto-5 Magnum shotgun was made in the year 1982.
Auto-5 'Magnum Twelve' from 1965.
50-600 usd
You will have to call Browning with the sn to find out.
50-550 usd