These are some excellent schools for your academic interests that may be affordable for you, should you gain acceptance to one or more of them:
Brown University
Carleton College
Cornell University
Dartmouth College
Hamilton College
New York University
Pomona College
Princeton University
Stanford University
University of Chicago
University of Pennsylvania
As you have suggested, you would like to take your chances at highly selective U.S. colleges. Applications to schools of your choice from the group above could certainly match that objective.