I second Paulís recommendation! It doesn't get any better than that!
In the mean time there are many experts on this site who would be more than willing to lend a hand. To begin with, simply ask the seller to send you pics of the VIN, Cowl Tag, and Engine pad. If all these check out, move onto the Transmission and Rear Axle numbers.
If you need help posting the pics send me a PM and I'll be happy to help you out.