Pretty much no gunsmiths "weld up" a factory barrel hood or lugs anymore.
Nobody really tightens up a barrel hood on an existing or factory barrel anymore.
The aftermarket "match grade" barrels are oversize in those areas and the custom smith will fit them to your slide.
Sounds like what you really need is a new match grade barrel.
That takes care of the barrel feed ramp (already throated and polished) - the hood the barrel lugs plus the bushing (already fit to the barrel) and the link.
If you have that done then you might NOT need to get the slide tightened to the frame.
In fact I would say unless it's "goose loose" then probably not.
Just guessing that what you really need is a "fit" match grade barrel with a mated bushing and the correct size link.
POSSIBLY...your frame feed ramp polished.
and a tuned Extractor.
That should cover you out and you should be good to go.