I just saw this posting. Sorry you haven't had any comments. I don't live in the area, but I'm not all that far away, and am actually in another (rival) university area.
What did you end up doing? My suggestion would have been to contact someone with an Airbnb and book through them for the first stay. Then you'd have a feel for the place and host, so you could approach them to ask about a recurring stay each week. Another option would have been to look on a Facebook housing group for the university. Just because it's geared towards students, doesn't mean everyone there is. Plus they have the medical school and other graduate programs, so your roommate may likely be a single person with a 2 bedroom apartment that is there even less time than you.