Re-Rack and Maytag
I have seen Re-Rack at my favorite ACE. It comes in white or grey, but not aqua. I needed some touch-up for aqua racks and after checking with a lot of appliance parts places, I found a funky shop that had some. It's Maytag brand, it worked well, but is much more blue and doesn't match the rack color at all. Fortunately, the worst rust spots are on the underside of the rack. The stuff is not cheap. It was around $18 for a small bottle (a plastic bag of new tips for the tines was also included), but a little goes a long way. It appears to be holding up fine though, even when subjected to the "Heavy Steam" cycle on my Thermador.
Unless your racks are totally rusted, this plastisol touch-up route would be the quickest and easiest.