$10-$15K may or may not be a good price. Sounds reasonable based on your description of the car and IF all the parts are there.
Best bet is to contact Pat Mical www.patsauto.com . He has a shop in Chelmsford, Mass and may be willing to help if you give him some business.
Also, just bec a car is in Mass doesn't neccessarily mean rust, but since the car has been neglected, it will undoubtedly have some rust. You just don't want it in the terminal areas. Check the entire undercarriage and rear support frame carefully with ice pick in hand. Here's a few photos of what you DO NOT want to see: http://www.panteraplace.com/page57.htm
Good Luck,
Kevin
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