Ah, yes, I forgot about Japan using the other side of the road So not so long ago in Poland it would be the same, BUT as Polish used car dealers do "magic", there were (and are) lots of RHD cars imported from the UK converted to LHD (that's why it's not so unusual to spot a Vauxhall in Poland ). Right now I think that they are still converted, but it's not required by law - an RHD car can be driven, normally registered and pass inspections.
EDIT: But do I get it correctly that cars over 25 years old do not have to meet various US legal norms?? That would be super-weird. In Poland if you import a car from the US you have to change it's headlights and indicators to ones that are up to European standards, no matter how old the car is (maaaaybe there's an exception for cars registered as antiques, but I doubt it).