i may be opening my self up to be raped here... but iam not sure what sort of price they are to buy as i havent shopped around at the minute , i thought i'd try asking on here first to see if anyone had spares !
good quality and just over a fiver a go plus postage from the US. If you only get 2-3 at a time there won't be any customs charges either (Ã'£18 limit).