Looks to be a post-war German police holster for a Hi-Power.
DWM was out of the game by 1940, so there’s quite a bit of age gap in parts on the pistol. Better photos will be the only way to give you a fair answer. A German wartime gun specific forum will be able to give you better answers, be it either of the Luger forums or the P.38 forum.
A refinished, mix-master will bring more than they once did in the current market, but don’t count on retiring on it. I wouldn’t expect for it to bring much more that 1.2K, at best, on a forum or auction. You may consider selling the holster separately once you narrow down what it is. Simpson’s recently released (and still seems to be) many shooter grade Lugers, you may compare what you have to their prices. The spare magazine, assuming it is legitimate, will add some worth also.
Best of luck.