Well, I'm not in the UK, but I'm down here in Australia, so I have even less range to choose from than you (the Xoom isn't even out here yet). Well, you could still order the zoogue one from their site, I think. I'm pretty sure they have international shipping, don't they?
Also, I recently bought a case off eBay that has fully adjustable viewing angles (via the use of velcro), like the zoogue but is only US$25. I think it looks really nice too, but I guess I'll find out when it arrives.
I can't post links, but if you search "Black Folio Leather Case Cover For Motorola Xoom Tablet" exactly, it should show up. It's the one with taylor swift in on the xoom screen, and the seller is "dcone_us"