1961 Chevrolet Greenbrier Van

 They made these with the rear-mounted Corvair engine. There's a rampside '61 Corvair van featured in Hemming's Classic Cars this month. This one was parked down on the Portland (Maine) waterfront, near the Casco Bay ferry terminal. It's a salty zone, but this van doesn't look like its spent too much time there.  Waterfront is the real Rust Belt.