Sorry to be a Donny Downer but I speak from some experience here and Powder Coating won't be an option. Powder Coat won't adhere to chrome and unfortunately, it is usually impossible to abrasive blast chrome off without damaging the porous metal, usually aluminum, the wheel itself is made of.
If any porous metal is exposed, the coating will "pop" during the baking process and leave ugly marks similar to paint fisheyes, only uglier and there will be no wet sand and buff process to fix them.
I can assure you you won't be satisfied with the result.
You can have the chrome and nickel chemically removed before they try to PC them but even if this process could somehow be accomplished without exposing porous metal somewhere on the wheel face, I'm certain you'll quickly find out it would be completely cost prohibitive.
But I could be wrong.