Up-grade to Mountain Lion from Leopard 10.6.8

Can anyone provide a link to enable the purchase of Mountain Lion in the UK??

I asked a similar question before and several people helpfully provided a purchase link, but unfortunately it was to the US store and although there appeared to be a facility to purchase Mountain Lion, it was in US $ (19.99) and required a US address, zip code & telephone number. One community member helpfully provided an equivalent UK link but I unfortunately lost the link before I could use it (when I say "lost" I mean carelessly deleted it!). Apologies for this additional post.