Surprised not to see any responses to this, as there are several. Best bet is to do a search on these forums, or to look in the back of a flying magazine.
I seem to remember that the company I used several years ago was Traffords, but it's too long ago for me to still have any contact details (or even know if they still offer it). At the time, they were very helpful. I applied for their standard insurance, but to include cover for acting as a crew member of an aircraft, and they did exactly what I asked them. When I got the paperwork and read the small-print, I discovered that they did not cover me for aerobatics. Since I'd planned on doing some aerobatics, I phoned them up, they charged me a small surcharge, and the new paperwork was in the post the same day.
FFF
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