flatwater

Well I guess I will be needing a new fornt rotor if I can get away with replacing just the one. The left one on my bike now rubs for about a 2.5 in. spot on the rotor. I can here it through my helmet at low speeds and it drives me crazy. Is there any real danger in driving it until I find a rotor at a resonable price? Where is a good place to find a new rotor? Any suggestions? Thanks