Fabrique Nationale (the name of the company) arms of war, Herstal, Belguim (place of manufacture. Brownings patent filed.
Not in the open market
Impossible to answer without a serial number and detailed description.
You gave use the maker- FN- but not which firearm- and the serial number alone does us no good.
I would also be interested in any information that you find as I also have one.
This is the Belgian firearms company Fabrique Nationale
fabrique nationale & Taurus
Fabrique Nationale d'Herstal
you have a 12ga Magnum made in Herstal Belgium by Fabrique Nationale in 1969. FN was the manufacturer of all belgian Brownings. auto5man