A really good friend of mine from my undergraduate institution (large state university) got into Brown, UCLA, Yale, and Washington with a GRE score around the low 700's. He's a Mexican citizen with a degree from a US institution. You need to stop worrying and look at your situation more pragmatically before you run yourself into the ground. Your US degree will help immensely, and condensed matter has a lot more funding than something like high energy theory or mathematical physics, so you'll be in a large pool. If your independent research is good, you may get noticed by someone at a top tier. It would be helpful to send extremely concise emails to a few senior faculty at your top schools to get their opinion, but don't write them an essay, they don't have much time to give to students that haven't been admitted yet. However, if you describe your work in a couple sentences and your credentials in another, you can gauge your chances (and perhaps even elicit some interest). You have a good shot to get into several good programs, so don't lose focus and screw up the tone of your application out of self-deprecation. If you truly had a bad day when you took the GRE Physics, then give them every reason to believe you by NOT obsessing about it in your application. Communicate that you know what you are talking about!
And you need to add the University of Illinois at Urbana-Champagne (UIUC) to your list, they are one of the best schools for condensed matter, and a very large program at that. My friend got into the program with GRE scores in the mid-700's.