I’m in Bath. If you do know of a good indy, nearby that’d be helpful for other watches.
If you need a good shop that has its own watch makers in-house, then Deacons in Marlborough, Swindon and Royal Wootton Bassett are the people to go to. They repaired my old Yema Rallygraf a year or so back after the mainspring broke, serviced it, replaced the crystal and polished the case. Cost me £460, which seems a lot for a watch I paid £40 for in 1970. One sold at auction in London in March for £3400…
I also have a Seiko diver, a SPORK, or SP045RK, stunning watch, face style is pilots watch, and they were only made for a while, mine was NOS, with box and warranty from a dealer in the Midlands, cost £650, with money my mum left me. As someone else said, it’s not too difficult to regulate them yourself, but a minute a week would be considered acceptable for a Rolex, mine was running at around a minute every couple of weeks, after I tweaked it, not quite as good now, but still more than acceptable, I’ve got a G-Shock that’s much worse.