I recently had my Z broken into through the driver-side window and I am now in the process of finding replacement glass. I have searched extensively in the Dallas, Texas area with no luck whatsoever. If anyone could recommend a dealer (online or otherwise) who would have window glass for a '73 I would be endlessly thankfull.

You're in Dallas, you have it made!!! Call All Z Car Specilalist and talk to Jerry, he will have what you need.