I can scratch this job off my to do list, covered my welded wood rack with some old tin I had laying around.
Have you ever checked the metal bin at your local dump? Seriously. Since I've been pulling saws out of the recycle bin, I've noticed lots of metal roofing that could be used if a person isn't super yupped out.
Good luck. Another thing. Find a large commercial project. They drop off metal bins to be filled at the jobsite. I scored enough metal in Moncks Corner SC to cover a huge rabbitry (rabbit barn ). Just had to put on my own hard hat and reflective vest.