Back in May of 2014 I was able to get the plastic headlights from RockAuto. Part numbers:
HP4656 and HP4651
The P stands for plastic. Since the car is garage kept and not driven as much as it should be I'm not worried about the lenses turning yellow. I will say though, they looked to be 20-some years old, but still new in the boxes.
There is a thread here about these headlights. A keyword and my user name should bring it up.
RemoveBeforeFlight