A cheaper solution would be to sand them down manually till all the flaking has come off (you can use a screwdriver like a scalpel on the worst parts), in the end you could have some parts with paint, some with primer showing and some with bare metal.
When you get the surface smooth enough to not feel any edge and tapping it you have a solid feel (no air buble underneath) you can paint with primer and paint or directly with high temperature paint.
It's not going to last as long as a professional job.
I did these for my winter wheels, 15" valver's speedlines. Mind that these have a much simpler design than the turbines.
They were in bad conditions with scratches, flaking, a lot of 10+ years old dirt.
I brushed them with metal wool till all the dirt was off and the worse scratches were smoothed out. The paint came off in many places, with primer or bare metal visible.
Then I used progressively fine sand paper till I was satisfied with the result. Then I painted them with two hand of high temperature matt black, with no primer. I've no idea the result would be with white paint.
Seems it worked as I already used them for two whole winters, with snow and ice, and they still are in good conditions. As I spend 20£, plus the 40 for the used wheels, and the time spent for the job, seems a good deal to me.
