I would be Jake, a WASPy 28-year old man from New England who speaks no Korean and wears 70s style suits, and is possibly recently unemployed.
The guide would be younger and prettier, speak better English, and dream of going to New York, which Jake would represent for her. Her English name would still be Sheena though so we could use the Ramones song at some point.
The bus driver would be young, handsome and stoic, and speak no English. I picture someone like Seo Inguk for this. He and Sheena would be dating or at least fucking, until Jake comes along of course.
The other passengers would still be two white ladies in their late 50s, possibly from the South instead of Alberta. Optionally there could also be an old Indian man or couple who takes lots of pictures and never speaks (or, better, only speaks once).
You can already guess how the film would play out. A lot would be made of instant coffee mix, how much taller Jake is than everyone else, and the crowds of schoolkids at tourist attractions. At some point Sheena would sing “빙을 빙을” in a noraebang. Jake would have a moment of profound realization on a mountain or something? Who can I pitch this script to?