Color sights
A colored sight will help with shooting against a dark background, but not really much help on a well lit range. A black bull and black sights makes for a little more difficult sighting. Perhaps try this-white poster board or white paper, and some stick-on orange dots from the stationary store. Get the ones that are larger-1 to 2 inches, for pistol range. THe background and the dot will contrast very nicely with black sights, especially if you smoke the sights for glare prevention. Then you have to contend with ammo quality and trigger action. If you want to paint the sight, you first must degrease it with alcohol. Pure isopropyl on a q tip. Then I would put down a base coat of white paint before painting it red or orange. Otherwise you will need several coats as the black background will make the paint look dark. Since you have degreased the front sight area, scotch tape should stick allowing you to mask off the area you want to paint for a neat job. If you use a durable paint, it will not really wear out that quickly. Serrated ramps hold the paint for a long time, unless you really rub the paint with solvents or oils. After the paint is cured, it will probably resist oil to some degree. Try enamel paints instead of any water based or acrylic.