Some of these designs are just cool in my book. As long as they're represented correctly no real harm.
As to the 1900 pieces. I'll bet that most/all of the "1900" parts are FNM 2300. Around the early 80's, weren't there something like 1000 of them, new, stuck in railyards in Europe rusting away as no one wanted to buy a car based on 50's technology? I know that there used to be a large availability of advertised mechanicals from the these cars (and their spares?) pretty cheap. Just a guess, but with all that mechanical stuff sitting around it got repurposed.