Welcome to the forum.
I like Sweden. Especially IKEA and Astrid Lindgren's tales.
Everytime I visit IKEA I want to become Swede
My wife says that her grand-grand-grand-...mother was Swede.
Did Sweden use any rolling stock from Norway? Or maybe Finland? If yes, you can use "Norwegian" BR52 steam locomotive or NOHAB (Di3) diesel.
As I know, Sweden railways have connections with Norway, Finland, Denmark (by bridge and by ferry), Germany and Poland (by ferry) so you can use some European cars.
As I know, in 1960s-1980s there was even the train Moscow-Stockholm (through Berlin)