The Virginian car looks very similar to the Bluford car, except for the diagonal braces on the ends (see the VGN logo) - here's one in 1952:
http://www.nwhs.org/archivesdb/detail.php?ID=40923The cars were rebuilt with Cor-Ten steel starting in September 1954. I am guessing the rebuilds were completed within two years.
So I should be good to have a few of these for 1955.

948 transferred to N&W at the time of the merger (December 1959), and cars from this class (VGN H8a, H28a on the N&W) persisted until 1974, though most were gone by 1970. I quickly looked through my resources and could find no pics of the cars rebuilt with steel, but this is what they should have looked like:
http://www.nwhs.org/archivesdb/detail.php?ID=14882EDIT 10/16/2016: According to N&W equipment listing as of 1/1/1969, 184 of this (rebuilt) class remained active on the N&W (gone by the end of 1974).
Mark