Your best bet might be to find blue caliper paint. It is a hi temp paint and with some diligence to get the surface clean, you can paint them in place
Found these, Hope it helpsI like that the R's have red Brembo brake caliper covers to complement the red in the stripes and badge. I would like to install blue covers to accent my stripes. Has anyone done this? Is it cheaper to powder coat the existing covers or buy new ones? I know the advantage of new ones is no down time. Any idea on cost?