I've made inquiries and a cloth bag with a Velcro closure would cost about $30 in materials and manufacturing time at $0 markup (as in labour and materials only). She'd need a commitment of at least 30 items for a test production run, otherwise, it isn't worth it for her sewing staff to manufacture the bags.
I'm going to work on prototyping one and see if there is interest, if so, and there is commitment from guys on here, I can ask her to do a first run. She has about 10 meters of blue 3 ply non branded Gore-tex, which she'll use for the first run. Prices would go up if a different fabric was requested/ordered.