I enquired about exactly this earlier in the year.
Best reports I got we're for Pedros and Baltic Wharf, both round the corner but not far away.
Don't have the links on me at the moment but a quick Google should find the.
There was a yard in Plymouth, All Boat Services, but they were about £2k dearer.
Baltic Wharf have the hot pad system so the job can be completed in 6 weeks or so.
I didn't have the work done in the end (doing it in Scotland)vbut would have plumped for Baltic Wharf FWIW.