I just finished the first color on an F-15. I was unable to get my airbrush working, and to make the end of the GB, I needed to paint the plane somehow.
The colors that I needed I found thru Poli-Scale. The first time that I have brush painted a aircraft and get the result that I did! I got almost the end result that I would have gotten with the airbrush! The way I did that was to use brush strokes in one direction only, and went over the area several times. AND I HAD NO PROBLEMS WITH THE PLASTIC REPELING THE PAINT!! I too have had that problem before using Tamiya or Testors Arcyrlic paints. The oil based paints I have also had some of that as well. After this experience, I think I'll be using Pol-Scale more often!
The silver color that you ask about; I have used some of Testors spray cans that are specificly colored towards a metal (steel, aluminim, etc.), or you can use a Bare Foil material (I have never used it, but many have). Check both out at your hobby shop in the paint area.