Without knowing much about it, I'd say it doesn't sound legit. Was there a Core Duo (i.e., not Core 2 Duo like modern laptop cpus) 2.33 GHz version used in the 17" MBP? If not, then I don't know how it could be so cheap.
from the ad it's a core2duo, said to be in pristine condition. I called the number i got a legit message machine. I'll call back in a little, if he answers i'm jumping on this.