May I ask why you wish to apply to "Ivy" schools? I know they are rather good, but what specifically about them makes you want to apply there? Good program, a certain professor, reputation? There are tons of "Non-Ivy" schools out there that are just as good, if not better. Try not to limit your schools based on their athletic conference, (even though it is known to be quite prestigious) as there are tons of great programs out there. That's as foolish as someone only looking to apply to Big-12 or Pac-10 schools.
Also, read the graduate school admissions 101 thread. It is difficult for people to tell you your chances of getting into an "Ivy" league school based solely on your GRE scores and GPA. I'm not sure with a masters program, but usually your research experience, recommendation letters, fit, and statement of purpose are more important (although GRE/GPA may get you over the initial screening at some schools).