Looking to STAGE(intern) while in Chicago !
Have you researched which restaurants you would like to work in this city? The possibilities are endless, but you should definitely start looking around and start trying to call a few places to explain your situation and see if they may be able to help. The worst they can say is no, right?
This may sound weird, but I also suggest looking through the F&B Job Postings on craigslist. I have helped many a friend (and myself) set up stages/jobs from leads I've found there.
You can call and try, but being they are the only 3* restaurant in the city I can almost guarantee you that they are flooded with applications and resumes. They can be picky. I would try to look up other great restaurants that are not as recognized as I feel your odds of success would be better with them.
Keep searching, calling, and leaving messages. Your biggest hurdle to overcome is that you are on a limited timeframe and most places that are hiring are definitely looking for something more than a one time 2-3 nights (including the places I work at). Nonetheless, best of luck on your search and hopefully you can find something.