Red wisteria isn't a wisteria but Sesbania punicea. I've not seen it for sale either. there may be a good reason for this :o)

Hi, it's probably because it's frost tender, although if the wood of Sesbania punicea have had time to ripen, may possibly survive temperatures down to 32f , if not for too long, otherwise needs a minimum temp of 41f, and best grown in a cool to warm greenhouse or conservatory, Derek.