50-1000 USD or more depending on specifics.
Your Browning superposed,over under 20 gauge shotgun was made in the year 1951;with the serial number that you have provided.
A shotgun.
No such model name in the Browning line.
Weight of the weapon.
What is it you are asking?
100-1000 USD
65-550 usd
100-2000 usd
100-500 USD
Impossible to do with just the sn in this case. You will have to call Browning.
Go to Browning's site, click on Support then date your firearm.
The prefix of 75x indicates that your Browning shotgun was made in the year 1975.