you'll have to dig thru this Chevelle ad to find the glass but there are other cross over parts there also
http://www.kijiji.ca/v-classic-cars/city-of-toronto/chevelle-gm-parts/1242216174?enableSearchNavigationFlag=true
corrected the link... thanks greaser
wrong link Ted......this one's the shop manual
Greaser - https://en.wikipedia.org/wiki/Greaser_(subculture)