Summit resplines. I don't know what you mean by cutting shafts from scratch.....
Your not going to find any one locally that "makes" axles shafts. They all start with a blank from a major mfg and cut/spline from there. Even places like Currie start with blanks....Look at your Currie, MW, Alloy USA etc shafts. I bet if you look close you will see a little AA inside a diamond stamped into the lip of the flange. That is an American axle blank. Yukon is not AA, their blanks come from India.
Ya I figured this much, we did one of these already but kept it factory width and had Moser cut the shaft for us, was hoping we had someone local that did it.