Museums are great places for model railroaders to visit to see the real thing when detailing models or, better yet, if the train runs, to hear the engine and horn or whistle and compare it with the model that has sounds.
Nearly every model of locomotive is preserved, fortunately, but some models are as extinct as the doo-doos. The UP’s M-100000 streamliner, for example.
Also, some museums have maintained rolling stock; the best being the Colorado narrow gauge lines which are operational museums with track. However, my guess is that some rolling stock too, are extinct, such as the tri-level open-type auto rack.
Are there any favorite models you have that no longer exist?
Take a look at http://exotic.railfan.net/ for info on rarer diesels - according to this two C-Liner A units survive, and a pair of Bs minus their power units. I think one of the C-Liners is a CN example in a museum.
I too mourn the lack of preserved Erie-Builts - my fictional museum line operates a C&NW example which has been rebuilt with an EMD power unit and Head End Power to work with commuter bilevels (that’s the fiction I thought up to explain how it came to run with these cars, it looks pretty good as a consist). The lack of DL109s is also a pity - as I understand it they were effectively “worked to death” during WW2, hence no surviving examples.
At last report, the Sharks still survive. D&H 1205 and 1216 are in private hands, stored in Michigan. One is mortally wounded, with an engine block failure, The other is intact. Maybe we can get Doyle McCormick to obtain and restore them after he finishes with the PA’s.