A while back I did some research for a fellow on the hardware in those sheaths and holsters of the time period. He wanted them for a recreation society. I found that some things like the "press the dot" snaps are easy enough to find, but other items are not so much. Those oval staples and the apparatus at the mouth of the sheath were evidently manufactured for the military only, unless someone knows a little shop in the alley in Borger Texas where the fellow has a bunch of surplus hardware.
In short, it is very difficult to fake one of those sheaths, unless you have a source for the hardware, then it makes them kind of not worth the expense eh?
By the way, those WW2 recreation guys are amazingly fussy about every little detail, their costumes are correct down to the type of thread used to sew on the buttons, amazing people.