It's configured like a 21-speed right now (7x3). Are those hard to come by these days? I have an appointment with the repair shop in town this afternoon. Hopefully they don't bilk me out of major dough. I wouldn't like to spend more than $100 - $125 total. The shop in town mainly deals in Salsa and Surly mountain bikes, but told me they'll be able to help me as well. I imagine shifting components are similar across bikes - Shimano and the other brand I can never remember.
Thanks everyone for your help!