I finally had time to check - the WGA-West library IS open to the public. Understandably, their collection, while large, is also limited. Whether they have Miami Vice scripts, much less unproduced scripts, is anyone's guess. Tho I suspect the chances are slim. Unproduced scripts do not seem to be part of their collection development policy.

Doesn't look like WGA-East has a library. WGA-West must serve both memberships, it seems...

shreve