I'm not sure if you saw my post:
http://www.zr1.net/forum/showthread.php?t=11833
I just went through this also. I bought a White Racing reproduction (He doesn't have any left) like Dandy97 is offering from a member here and am very happy with it. There are slight differences between it and the OEM glass, but it is much closer than a standard C4 windshield.