While in the navy and stationed at Bremerton, I do recall seeing a yellow GE 80 ton ( or so) switcher as below:
Now I do not know how many the Navy had US wide, but I am sure a little bit of internet searching would turn up an answer.
Further, this is a double whammie, because you get a "Navy" loco and a Navy load.
The other cars I would like to see would be some of the DODX cars used to transport spent fuel rods and other "reactor stuff". I did in fact get to see quite a few of those cars out about 60 miles West of Idaho Falls when I was in Nuclear Prototype school in the late 80's.... Those are some really interesting cars.