you could just buy any one of the looms from halfords (e.g. for taking Ford plugs and turning them into ISO plugs), and chop off the non-ISO end...
Could work out more expensive, but I guess with shipping from a 'net site it probably won't.
For which wires are what I guess Mr Haynes might help, or I'll be attempting to figure out where I have a dodgy earth/live to my HU later (someone's hard wired ISO plugs on, but since I fitted my sub I think I've disturbed something as it cuts out when asked to pump out high power, even with sub outputs turned off.) so I could probably tell you....