I would reccomend shopping for your primer and paint at the supplier for the local body shops. See what kind of epoxy primer they carry, You can usually get the professional grade stuff in rattle can form, or if you have the capabilities to use a spray gun go that route.
Our local supplier was very helpful in closely matching the factory silver in both a single stage or a base-clear(requiring spray equipment of course). The clearcoat comes out much glossier than the factory finish but it is also the strongest paint topcoat you can apply (no pigment to weaken it) short of specialty finishes or the powdercoat.
All that said, I've had suprisingly good, long lasting results with a cheapie rattle can (really, how much fowl weather are these going to see)
Remember, the nuts on the ends of the spokes are likley to need adjustment in the future. Just somthing to keep in mind while painting.