I need help identifing this .22 single shot training rifle. Across the front of the bolt on the reciever is marked; Gustloff-Werke Waffenwerke Suhl Mod 317K. On the barrel is marked; Fluss-Stahl Krupp Essen kal .22 long rifle. There are two Eagle over N proof marks. The eagle does not look like the usual Nazi eagle. The barrel is 26 1/2" long, the bolt has a Mauser style safety. The stock is beautifull walnut with checkered pistol grip and finger groove forearm. The rear sight is adjustable to 200 yards or meters. The butt plate is marked BSW.