http://www.overclockers.co.uk/showproduct.php?prodid=CB-033-AK&groupid=701&catid=48&subcat=153
?
EDIT
Ahh, just seen your PSU only has 2x PCI-e connectors, which will be going to your gtx 275 :S
They're not on ocuk, but why not try a molex to 8 pin adapter?