Hey, where abouts are you from? There are quite a few places around here. There is a car audio shop just at the back of BHS in woking, theres another place in west byfleet just over the m25 bridge on the right hand side (visiable from the road) and i think there is a place called top banana in farborough, if thats not to far to travel. hope that helps. Failing that you could search on
http://www.yell.com