Don't see why you couldn't. You could easily stitch a few bits of webbing together as a compression harness with folded loops for the quick release bits and a clip to hold it fast to the support too, if you wanted to mimic how the carradice bags attach
I was thinking I could use the loops you get on alpkit dry bags combined with the support and some bolt on saddle bag loops. I don't have any personal experience with the supports though, how sturdy are they?
I don't actually like their bags. Not a fan of the retro Aesthetic, I already have excellent dry bags, and the supports are about £25.
I was thinking they'd be a bit more stable than my restrap and I can easily just leave it on the bike all the time.