Re: Any warmoth-type builders who finish with nitro?
Musikraft can send your body or neck to an outside finisher named Orion. B. Hefner finishes as well, though he is overpriced, and his body shapes and specs are pretty far off from historical specs. Not a good choice if you are looking to make an "accurate" copy of an instrument of a certain year. Plus, he is a real ****in' ass-hole if ever there was one. R.S. can do it all for you, though they will cost you. Mark Jenny can do what you want as well, although he will not do factory-fresh finishes, only relics. I don't know if he uses Allparts bodies or what. You might want to ask him that.
Honestly, if I didn't do my own finishes now, I'd order parts from Musikraft, and have finishing done by R.S. IME, they are each the best of the bunch in those respective categories. Since you don't want to do something like that, I'd recommend just going the Musikraft/Orion route.