The action is very likely made in Belgium and if you remove the forend, it may be stamped PD on the front which most take as a “Public Domain” stamp indicating that the action patent had run it’s course.
Usually, the many retailers simply engraved their name and address on the barrels with not much else to differentiate one from another. Sometimes sights, sling eyes and some stockwork were executed in a house style but often just add a name and out the door it seems.
I’ll go back to the books on these Farquharsons to look for specifics.