I had no idea they were that new. Thanks for that.
Here are some other options in 40' composite drop bottom ("general service" gons-
Fine N Scale "Caswell" Gondola (primarily ATSF, not sure who else may have used "Caswell" doors and hardware). But the side pattern is fairly common for early 1900s gondolas). Resin and brass kit.
http://www.spookshow.net/freight/finecaswell.htmlIntermountain USRA 40' gondola. The USRA cars were widely used, and "clones" were made well into the 1920s. The most widely used of the various options. Lasted in MoW well into the 50s. Many were rebuilt by simply replacing the wood with steel sheet- simple to do if you can find one of these in undec kit form because the wood sides are separate parts from the frame.
http://www.spookshow.net/freight/imusragond.htmlThe Roco/Atlas/Walthers/??, and most recently, a Bachmann copy. Ignore the 1956 build date in the Spookshow photo- in the 70s, manufacturers did not pay much attention to lettering details. My belief is that most of the cars of this design were WWII era "war emergency", although similar cars were constructed during the depression to save costs. Downside to all of these is that, as was practice when they were designed, these have the common Roco boxcar underframe, no modeling of the drop bottom.
http://www.spookshow.net/freight/atlasroco40obgond.htmlhttp://www.spookshow.net/freight/bach42obgond.htmlOne other option, if looking for something 1900 or earlier, or for MoW- Fine N Scale makes gondola sides to fit their truss rod boxcar. Not drop bottom, but it makes an believable early car or in MoW service. Or as a "trash gon" at a railyard into the 50s.
http://www.spookshow.net/freight/atlasroco40obgond.htmlhttp://www.spookshow.net/freight/bach42obgond.htmlMTL and Trainworx make more modern, steel, drop bottom gons.