Pennsy never had any offset side cars. The car itself fits your era, in other roadnames. However, a coal train would probably have a majority of PRR cars in most cases.
the car at the museum shown in your attached photo is a PRR GLC hopper in a paint scheme older than the circle keystone. It would be an appropriate car also for your era but starting to phase out. The MTH car is a very good model of the Western Maryland Fishbelly (and some others) but does not match the PRR GLC.
Atlas did the USRA hopper in 2 sets of PRR circle keystone. but as Bob mentioned, PRR only had about 300 of them and 30,000 of the GLAs.
The weaver car is a model of a modern longer 2 bay car based on a prototype I think built by Pullman Standard for the L&N. I don't think too many other roads had a modern welded 2 bay car like that. they do have the advantage of being a good bit cheaper than the others so make good train filler.