Carmady,
There are two versions of that holster. The WWII era (and likely Korea) "M3" versions, have only one strap. The Viet Nam era and later "M7" versions have an additional strap, like you see in the above pic.
This may give a better idea how the straps work.
Pacific canvas and Leather has versions of both if you want a "user". Personally, Id keep the original somewhere safe, and use one of the better replicas for use.
I have a PC&L, as well as an El Paso, both M3 versions, and I also have an old Cathey Ent. M3, which I like the best.
The El Paso is a nice holster, but pricey, and was very oily when I got it, and took some work to get it to stop "sweating" oil.
The PC&L is the cheapest looking, but still quite functional, and probably the best deal dollar wise.