Atlas made a good HL 2 bay that would work. Also, there were many, many 3 bays in service on the N&W during the steam era. I'm not aware of any 3 bays that were correctly modelled in 3 rail.
Below is a link to classes and numbers and years of service for N&W engines and rolling stock, including hoppers in the steam era that have been imported in 0 scale, many are 2 rail. If you scroll down past the engines, passenger cars, freight cars, etc. you'll get to the hoppers. Most have photos included of either the prototype or of a model.
