You can get spray cans of "Wheel Paint" in various brands and another option is to use Epoxy spray enamel intended for appliances ,it holds up a lot better than plain enamels will,ditto for the wheel paint...
Though an off white paint will look better than bright white,I've found the bright white dulls after awhile and becomes more cream colored than it looked at first due to the suns UV rays and dirt abrading the gloss...wouldn't hurt to put clear over the paint after it dries a few days completely..