I'm not sure where you can get them over there. I know a member here actually ended up mailing of bunch of them over to one of our UK members. I did a bit of a google search and came up with the fact that Acu-Rite is a brand name held by a company called Chaney Instruments out of Lake Geneva, Wisconsin. Here's a link to their contact us page. If all else fails, heck I'd email them directly and ask if their product is distributed in the UK or if you can order direct from them. Never hurts to go direct to the source.

http://www.chaneyinstruments.com/pgs/contact.htm

http://www.chaneyinstruments.com/pgs/inout.htm (you want the one pictured here on the far right, the indoor/outdoor digital thermometer - retails in the States for about $12.00 in american currency)

Hope this helps.