From what little I know about the RPI situation, I believe that the RPI students involvement in FIRST has tailed off considerably (this is basically only stuff I've heard through other people). I also believe that RPI gave financial support to team 250 last year (and in the past). As for other teams in the area, I don't believe there are any. Your best bet would be to check with FIRST however. While the Dean may recommend just supporting an existing team, personally, I'd recommend the opposite, if merely for the reason that more teams is always a good thing. Given that you have experience with FIRST and the Dean doesn't, you may be able to convince him that starting a new team is the way to go. If you do so, I would definately suggest finding some sort of faculty (staff are better than professors for this) to help champion your cause against the buearacracy. It helps quite a bit.
Matt