These lovely cards are blank inside and will raise funds for the UK CKCS club health fund! They are good value, £3 for a pack of five including postage (not sure if that's postage outside the UK though!).
Order here:
http://www.thecavalierclub.co.uk/fund/cards2.html
Order here:
http://www.thecavalierclub.co.uk/fund/cards2.html