No worries about the paint, if you are not any street, drag, or track racer, type of paint is not a problem, just use any better quality 2K paint, Glasurit or PPG are just fine. About the cleaning, if you are on the way to remove and disassemble whole calipers, sand blasting is the best option for cleaning, just keep in mind that you will need somehow to cover all vital parts such as cylinder, piston, nozzle openings.
I recently sand blasted mine, all rusty parts and bolts were zinc plated, and calipers were primered and refinished with 2K Standox (R77 Formula red) paint. This is not the first time for me to paint the calipers on this way, if you stay out from overheating and occasionally clean them they will be always like new.
I must mention that this type of work is not easy DIY, it takes a lot of time, money and of course steel nerves, but the result was pleasure...