I know this is an old Post, but just in case someone browsing through may want to know about these Oklahoma Holsters, I can tell you about mine.
I just purchased an Oklahoma Holster and Cartridges Belt. I wear a 40" gun belt. Usually they will be adjustable from 2" either side of what your gun belt size is. The Oklahoma Belt is 40" to 45". SO I'd better keep my weight up or lose my belt. The bullet loops need to be stretched. At least they did for my .45 caliber long colts. The holster was flat as a pancake, so I doused it in a sink full of water a few times. Took my Single Action Revolver and vasolined it fairly well. Then wrapped it in some saran-wrap from the kitchen, and stuffed the gun down into the wet holster, and let it dry for a few days. Now it looks good, and my gun fits perfectly. For $68 you can't beat it.