odd USAF Model 13 holster

:madsmile:Howdy here are several photos of Air Force M13 Aircrewman flap holsters [ and issued with the model 10 2 inchs issued in 1960 and the model 56 ] , one is a odd ball in that it not marked USAF , I had believed until now only Milsp [ Milawalee Saddley] and Servise MFG of Yonkers were the only manufactures of these holsters .Milsup holsers are not marked Milsp , but do have the 55D3513 part number on the side and are not of the quality of the Servise MFG holsters .Servise MFG of Yonkers are marked Servise MFG of Yonkers.
This odd has no marking and is again not marked USAF , has anyone else seen a holster like this ??
please post , rooster
heres the odd ball with shoulder strap
https://www.milsurps.com/images/impo.../03/af11-1.jpg

here are two Service MFG holsters
https://www.milsurps.com/images/impo.../03/af12-1.jpg

heres a MILsup
https://www.milsurps.com/images/impo.../03/af13-1.jpg

here are a Milsup on the left and Service MFG on the right , compare the flap studs and snaps see how they different .
https://www.milsurps.com/images/impo.../03/af14-1.jpg

and heres un unnamed odd ball its like a cross between to ones above ,
https://www.milsurps.com/images/impo.../03/af15-1.jpg

any thoughts please post , rooster