Chrome and aluminum like foils for making models are available from many sources, like ebay or online hobby shops. I have seen it at Hobby Lobby if you have one in your area. I tried some bare metal foil on one of my cars and wasn't real happy with the results, I don't think it is made to stand up to the environment a real car experiences even if that car spends most of its time in the garage and only comes out on the nicest of days.
Works great on models though!
It's cheap, so it is worth a try, you can always scrape it off if you don't like the results and look for a plan "B".
Good luck!