The Dodge Sprinter looks like it could make a great survival vehicle, but it's not inexpensive, and it isn't available in the US with the 4 cylinder diesel, just the 6.

A long wheelbase Jeep, like an M170, with a small air cooled engine, like a 20HP Honda, a big gas tank, and a synchronized transmission, would be nice. Light weight, no bells and whistles except manual 4WD, and a tiny but modern engine for quiet running and long range.