This model dates back to the early days of N scale (late 60s / early 70s). Atlas and Rivarossi parted company in the late 70's, but these cars lived on for years after that - showing up in various Arnold-Rivarossi freight sets. They presumably vanished when Rivarossi went bankrupt (circa 2005).
I'm not sure what specific prototype these models might be based on (if any), but going by the number of side panels (six) and the trusses next to the doors (which slope away from the doors rather than towards them), the prototype is likely an ACF-designed "Howe Truss" box car.