i would just do them yourself and do them right

http://www.eastwood.com/underhood-engine/exhaust-paints.html

you probably will not get your money back from the baddies even if you sue them.

use the eastwood header paint it lasts like 10 years for many people.

somewhere on their site they have a howto for restoring exhaust manifolds, some of the info there as to what products you can use could be adapted to doing your header project if they are rusty and rough