I think the OP is confused on this (or, just not listening).
Not only is naproxen Aleve, but there are generic versions to be had in every Walmart, Target, and CVS in the country. Even if the OP needs a higher dose, she can talk to her doctor about possibly taking extra pills. I do NOT recommend doing this without an MD's approval, but my Dh did it with ibuprofen when he was having knee issues (with doctor's permission, of course).
OP, I would be doing everything possible NOW, to get in better shape for your trip. As others have said, Diamond Head might not be in the cards for you, but there are plenty of things to enjoy in Hawaii that are less demanding.