Im with elephant.co.uk, My car is 2004 cooper, with coilovers, non standard alloys, sound system induction kit declared, Im 19 and got 1 year no claims and it cost's me £1121 per year, in my own name!!!
Elephant dont care about mods, aslong as you declare them, Theres a huggge list on the site of extras!! Also,
www.confused.com are usually good, They search about 20 diff companys who deal with your criteria! hope that helps!!
luke