No luck after several months? Have you considered just painting them yourself? I was taken aback at how thin and fragile the blurple paint is on my wheels. It matches my frame though so if I was going to do anything about it I'd paint them the same blurple color (assuming I could find that color in a spray can). Unfortunately, powder coating (baking the wheels at 180-C/350-F for 10-minutes for a polyester coating) requires new seals and bearings adding a lot to the cost. I painted a set of gold wheels gloss black previously and they came out looking great and the finish was still nice even after a tire change up until I sold the bike. Alternatively, you could fully prep the wheels and ask an auto-body shop to spray them gloss black when they spray a car the same color (which they'll likely do several times each week). You'd get a very high-quality paint then without having to spend much money.