I'm not sure about anything in Bristol but Nicky T from Planet Eclipse recently underwent a Intimidator training course and is now qualified to repair them. I'm not sure on the the extent of the service that planet could offer (i don't think they sell any Timmy parts yet) but it probably would be worth giving them a ring. Unfortunately you'll have to wait until Monday at least as Nick and co are all at Amsterdam at the mo.... along with the guys from Smart Parts Europe. Which has kinda pissed me off as I desperately need a new emergency release valve for my impulse, grr.
Also there is NPS Europe, again, I'm not sure on the services they offer but they are probably worth giving a ring. Phoenix also deal with Intimidators but I'm not sure if they still offer support on them but it doesn't take much to pick up the phone and check.
Here's the numbers if you want 'em
Planet: 0161 872 5572
NPS Europe: 0870 350 0055
Phoenix: 01543 451454