The best thing to do is peel off a bit and take it to your favorite paint store and have them mix a bit for you. Barring that you could try Appliance White Gloss Enamel. That should be a pretty good match. My question would be, why is it peeling? If it's from mechanical damage (i.e. scraped off) then a good sanding, some aluminum primer and a good even coat of enamel will fix it. If it's peeling because of poor paint adhesion you need to strip the entire thing, clean it, sand it, prime it, then paint it. Whatever you do be sure to use a good primer that states it's for aluminum. Otherwise, you'll be doing this again soon.
You are very right about one thing! There is only one black but there's a million whites.