Comments I found led me to the POR-20 Heat Resistant Paint. I think it comes in black and aluminum (silver). I used the aluminum. A pint easily does two manifolds (probably four). It brushes on easily and looks good. You cure it in the oven. Rated 1400F. After about 10 miles it still looks good.
The truck is in the paint shop, so that's all the miles it has so far.
