Phone these guys up;

01992 715 900

Company is called Group Componants, based near me, but 99% sure they do mail order....

They will have ANYTHING you need, and I know they will have the sockets as they have fucking HUGE sockets in their display cab (and when I mean HUGE i mean nearly a foot in diameter )

Also they will be cheaper than ANYWHERE else, specially Cromwells, Halfords, Partco, Browns etc.... Even inc postage they will be cheaper