: From a UK perspective please. What does this usually entail? And is
: there anything to watch out for when servicing a vintage? Any
: info appreciated.

£225 for a 7730 including new mainspring & crystal. £215 for a 7733 including one new gasket and an internal screw both with Rich Askham. Royal Mail Special Delivery (insured) works well, and instead of going to a depot 30 miles away it's left at the local Post Office 10 minutes walk away if I'm not in (or FedEx etc. did their usual high speed drive-by), but the maximum insured value is is now getting a bit low for Heuers of that era. Besides Rich there are a couple of other UK watchmakers I have heard good things about.

Valjoux spares are available at reasonable prices (FSVO) and the actual work will take about 2 weeks elapsed plus waiting time in the incoming queue. I always say "Take your time, getting it back right is better than getting it back fast."

To avoid: sorry about this, but TAG-Heuer dealers are still on that list. A local Rolex dealer does a fine job of crystal replacement for me now at an extremely reasonable charge.