CPC don't do online, but they do telephone ordering if that's any good
There are a few options, but be aware that orders under £30+VAT attract a handling/shipping charge of between £3-5 (used to be £6 I think).
Profigold RGB component lead
AV04615 - 10m - £28.22 (it retails as the PGV339, usually for £70 - Superfi, accessorystore... etc)
May as well add something else on as well for a few quid to avoid the £3 postage charge (order one of the cables below - essentially it's free

)
Alternatively, try
AV02031 - 10m single RG59 (75ohm) phono-phono lead with metal GP plugs - £2.92 each, just order 3, and add £5 for postage.
Tel No is 08701 202530, and prices are plus VAT!
BTW, 10m is a long way - how big's your room ?
