I would definitely have someone who knows C2s look over the car for you, especially the frame and birdcage. Ask me how I know.
Below are several sites that you can take a look at to gauge the asking price for various models (not to mention the 87 C2s on ebay).
There are 142 mid-years for sale on this site:
http://usedcorvettesforsale.com/corv...or-sale-2.html
This site has over 50 mid-years:
http://www.vettehound.com/geo/classifieds.php?a=5&b=342
This site lists a bunch of mid-years and they also offer appraisals (advertised for $69 with info you provide- I would personally ask what it would cost for someone to look over the actual car).
http://www.vettefinders.com/index.cf...s-for-sale.htm
You can also post this request on the C1-C2 section of
www.corvetteforum.com.
Shoot me a PM if you want to talk.