Hey Dave,
The only all fiberglass body shell I know of is the one from the Roadster from PTeazer. Here is a link for more info.
PTEAZER - Your Source For PT Cruiser Parts, PT Cruiser Conversions, PT Cruiser Modifications, PT Cruiser Aftermarket Parts, PT Cruiser Accessories and Panel Conversions.
Ray (The owner) is a bit pricey, but he does a lot of fiberglass work, and has all the molds, so he is probably your best bet.
Take it easy,
Candyman