They did the strip and spray for me. Was impressed with results as I've previously mentioned - you're welcome to inspect end result on the frame. Took about a week and a bit but to be honest if I'd hasseled them about it probably could have been quicker. Very informal, paper-based set up they have.
Not sure how much they will be able to do in terms of structural welding, I think cosmetic domestic metalwork is more their thing - fireplaces, radiators, gates etc. But I can recommend you an experienced bicycle and motorbike metal basher / welder I know through ERC who has a workshop in Portobello. When I get round to it, he's going to weld me a new steerer onto my fork on the still-to-be-complete singlespeed project.
I'm not sure if he does stripping/spraying. But think he might. I'll drop you his details.