This might be a no-no but this is what I have done for rust. I scrub the metal to get as much rust off and use heat-resistant BBQ high gloss or matte paint (it comes in a can and uses a brush to paint on like regular house paint). It super thick. I have used it on metal sewing machine pedals and they look great. I once had a iron bed sand blasted, looked great, but cost me more than the bed cost
