I've volunteered at our local museum that does reenactments etc. Did you know that the dress the pioneer women used to have had pockets? They did, but they weren't attached. They made a pair of pockets on a string that went around your waist. I think they wore them on the inside of their garment. Remember their garments didn't have any zippers just ties and buttons, snaps and eye hooks. You could always make that kind of pockets!