I just received a Lefever 16 ga. in an inheritance. The only markings on the gun are "Lefever Nitro Special" "Lefever Arms Co. Ithaca N. Y." on top of the barrel. I can find no other markings on the gun, no serial number or model. There is no ***** number. The gun has a flying goose ingraved on each sideplate, the grip is embossed/painted not knurled and the butt plate is black wood. Can you help me with the age or value or maybe where any other markings may located?