Get hold of the guy who bought out Mitchel motor parts. in Georgia.

I was there several years back and he had A LOT of early sheet metal laying all over the place. Most of it outside so it will be surface rust . but the good part is that stuff is really heavy gauge so it might be savable

No idea what or how much or even still has any of it. But it might be worth a shot.
Either way, good luck, You gonna need it