Since they discontinued it in the US quite a while ago, and I believe they said customer satisfaction with the device was low, I’d be surprised if they released it in the UK. They certainly won’t sell it directly anymore to anyone, though that’s simply because it’s a discontinued product.
But as @Joel_Ek explained, there are also very good reasons why specific products are restricted to specific regional markets.
Your only option is probably to try eBay, but even then it’s a use at your own risk situation, since the product is no longer supported. I don’t think they disabled existing devices though, so there may still be usable ones out there.