Some more/better pics would be nice. The mag release lock appears to be an early version without screw slot? I see a short hammer spur. That gun must have been "taken out of service" very early on, or it would have evidence of the retrofitting and updating that was done shortly after the M1911 was introduced.
Well it is clear that this is orginal pistol made by colt before the end of world war II ( Because of the holster ).
All military Colts were made before the end of WWII, but the black holster could be either a dyed holster that was orginally tan or brown, or it could be a later holster, made after the army changed to black leather gear (mid-'50s).