If you do decide to paint them the screw holes have circular rubber grommets in them. They are easy to remove for painting and then putting back after the paint has dried
I sanded them down well to remove all the gloss and then used the following products. I applied about four thin coats of each, 20 minutes apart and then dried overnight in a warm area.
From Amazon :-
1. JENOLITE Brake Caliper Paint | BLACK | Restore & Transform Car Brake Calipers
2. E-TECH XHT High Temperature Cleat Coat Lacquer Spray Paint - XHT006C