The XT660ZA was actually an official UK model back in 2011 (the year it was released). It only hung around for that year and was removed from the range in the UK for 2012 simply because nobody bought one! The rest of Europe seemed quite happy to buy them. In fact in some Scandinavian countries you can only buy the ZA.
So theoretically, if you're looking for a UK spec ABS Tenere, there will be some (maybe a handful) out there, although they'll be about as easy to track down as Lord Lucan.