TrinityRail has a 66' Mill Gondola as a current freight car.
https://www.trinityrail.com/pr...x?id=34&catid=30
FreightCar America has a gondola, but they do not have close-up photos posted.
http://www.freightcaramerica.c...x.php/manufacturing/
National Steel Car has gondolas with distinct ribs and undersides.
https://www.steelcar.com/products/gondola
Andrew