Ok I got to thinking. What do the windsheild repair outlets use when filling rock chips?
Found a few repair kits for windsheilds on ebay, but are sort of costly.. but .. did find some of the resin they use. Check it out:
http://cgi.ebay.ca/ws/eBayISAPI.dll?...2BSI%26otn%3D2
For $30ish it might be worth a try????