I guess a machine shop could fab up something, but I don't know what the exact process is to cut the correct tapered splines into a hub. My experience with machine shops has not been good locally. I have paid ridiculous sums for seemingly simple tasks........almost like they don't want to bother.

I would start by eyeballing the two wheels and see what makes them different dimensionally. Then maybe take those two parts to a machine shop and asking what needs done to make them mesh.

Don