Some take PayPal too.
I buy from Sportys and have it shipped to the UK. Mind you I use my Bank of America visa debit card which is registered in California - but they still ship to the UK. I did ask them about liferafts but didn't get a response, I guess they are dangerous goods.....
FTR I use the BofA visa debit card worldwide and use my UK debit cards worldwide and have never had a problem....