As I said before, it's no paint required, not no color available.
Steel can be made in several colors
Electrochemical and chemical finishes of stainless steel | Gasparini Industries shows you what colored steel looks like.
I'd assume there will be multiple color options from the factory when these things go into production.
So I could see doing a blue steel with a darker blue partial wrap (front of the vehicle and most of the side dark blue, work surfaces steel blue, no wrap in the cargo area.)