If you are flying an N-reg on an FAA licence and you have done the single pilot ticket you can fly wherever you like privately single pilot
I know of plenty of people that would disagree.
For a definitive answer, ask your authority. And then your insurer.
(two out of three, airspace doesn't matter).
Be wary of "the two out of tree rule". It's an oft quoted flying club maxim but non-existent real world rule. At best it's an inaccurate, potentially misleading, generalisation.