The mistake collectors make is they think a pouch or other piece of equipment has to be the same date as their firearm. The pouches and everything else was in one large supply system, so you got whatever was on hand at that unit.
For instance if you were just issued a Brand New Carbine in 1945, you could have been issued a pouch from 1942, 1943, 1944, or 1945.
I am not criticizing those that want to dress their firearm with certain dated equipment; I do it too. It is just that what we have in our minds is not at all the reality of what went on.