There was a few variations of the colours for these models,but if you stick with what vccomm has suggested you should be good and close to the original colour.
Generally with any top coat (on metal) primer should be used.With hammertone paint you can paint without primer,(I usually don't myself)as if you use primer you really should scuff it up with 400 grit wet and dry (or higher) before painting.
So I guess that's up to you,hammertone paint will stick to metal without primer,but should really use it.Just depends on weather you want to or not.
