There's a YouTube channel by a young flyer called Matt Guthmiller I quite enjoy watching. There's a series of videos he recorded about piloting (and co-piloting) a Cessna 210 from the US to the UK (and beyond). This is the playlist (I think it's in the correct chronological order):
https://www.youtube.com/watch?v=W9Uf-ynoDUE&list=PLoruKoPAfK...
I think at some point in the journey they also needed to use oxygen because they needed to fly above 10000 feet. Looked like quite an adventure.