Parts list for S/N B0557. Bolt BB7448 Firing Pin Retainer D7531 Firing Pin A 7341 Extractor G 1293 Trigger Housing B 0839 Hammer C 4251 Mag Assembly O 6267 Barrel 0 217K Barrel EXT 0 217K Any help in finding out if these parts are correct or not would be most helpful Dan Gilliam