Do a search for a "metalizing gun" They were used to coat aircraft cylinders with aluminum in the '30's-'50's so there should be some floating around.

They are a pretty cool tool. The one I tried used aluminum or brass but might have been able to use steel. It connected to the oxy/act welder and shop air so it was easy to run except for the whistle of the air turbine that fed the wire. The strangest thing was the metal went on cool. We metalized a styrofoam cup with not problem,