At first I thought this was a Nomad.
I thought all two-door Chevy wagons from the fifties were Nomads.
I knew this was a '58 because of the tail lights. However, when I went to look it up, it turned out that for 1958, the Nomad was only available as a four-door! Quel mystere!
On the same page (first link above), I discovered the Yeoman, which was available as a two-door for 1958.
However, the wagon in this picture does not have a C-pillar, which is the last roof support before the back of the car.
The windshield supports are the "A" pillars, the rear of the front door the "B", etc. Quel Grand mystere!
-Wikipedia