The value of a 12 gauge Browning Citori Pigeon Grade is actually dependent upon a number of factors. Some of these factors would be the age and condition.
50-5000 USD depending on specifics.
What gauge and grade is it?
In 90%+ condition about $700 for a 20 gauge and about $550-$600 for a 12 gauge.
Check 1966 gun catalogs
Around $5000.
100- multiple thousands depending on specifics.
Depends upon condition and area of the country it's for sale.
100-10000 usd
Info available on Browning's site.
A Browning side by side 20 gauge shotgun in Grade I,with a original finish of between 70%-90% will bring between 1,000-1,800 dollars.
You must call Browning to find out what grade it is.