Blicero HA HA the bug finally bit you. Your Mauser byf44 B block P.38 was made in December of 1944 and looks like a nice one. Make sure the locking block has the last three digits and the block letter suffix stamped on it. The holster is for a Lugar P.08 as stamped on the holster. The maker code cny 1940 WaA100, the maker was C. Pose, Whrausrutungen Berlin-Ost, Boxhanger Strasse. You did good on the holster. It's a rare one to find. Open the top flap there should a leather pocket the Lugar takedown tool. Ther should also be a also a leather strap to lift the Lugar out of the holster inside the holster. Give the holster the smell test it should smell like old leather not shoe polish.
This gun was probably picked up out of a pile of captured weapons and was matched up the first holster the soldier came across. As most grew up hearing about the Lugar from their WWI relatives. They assumed the P.38 was a Lugar too, The P.08 and the P.38 stamp on the holster did mean anything to most of the guys so if they had a P.38 without a holster they picked up the first holster they found.