Are you a US citizen? The british council website has a whole section of scholarships that are available to US students who want to attend UK schools. You can even list Cambridge University when you fill out your fafsa. My other suggestion would be to go to the school website. The school has a lot of scholarships that go out to international students from all over the world. Some are attached to what you want to study, so it makes the playing field a little bit smaller. Good luck. That is a great ambition. Just keep at it. If you want it that much, I have faith you will find a way.