This one looks like the best deal to me:
$9.99 each and they offer worldwide shipping.
Usually, the barrel size is the difficult spec to verify, but these say that they are right on the money.
I appreciate the response, but I need a UK supplier
i also don't want one that's liable to overheat and/or damage the box, simply because it's offered as a cheap alternaive
do FSP not supply them to the UK market?