$2 US ea, minimum of 24, they are 2 1/3 inches in diameter, not sure on shipping to the UK, but at $2 US each (thats wholesale), thats $48 for 24, say $20 or so for shipping $68 .. round up to $70, then shipping costs to the person, 5 bucks? ... $4 each plus shipping (ROUGH ESTIMATE BEWARE :P)

Regards,
A/V Dept.