The guy taken over would be David barks. Toms dad. He did some wielding on mine and rebuilt the rear section off my sill very well.
New wings are crazy prices, iv got two on mine. And one been fitted slightly pissed to have it corrected iv had quotes up 2 £1200 !!! I know people who paint and fit new wings for around £100 a time on normal family cars
A repire shouldn't normal require the wing removed, however it all depends on how wear its rotted. If painted and protected correctly most likely the wield will rust next. Suspect most will still have some filler work after the new metal.
Cheapest way to do this is part off a full respray. Which I know u have plans for In the future. In the mean time I would do some DIY to make what u have last till then