This jogged my memory as the Rifle Shoppe has a set of French lock castings with a similar stamping on the plate. Lejay - Duclos. From "The French Trade Gun in North America 1662-1759" - " Information pertaining to the association of the arms merchants Lejay and Duclos at St. Etienne is limited. Buigne mentions that they were actively working in 1720, although by 1748, Lejay's widow had taken over her husband's business and was attempting to become an officially recognized entrepreneur of military weapons in this town. "