It took a while, but I finally tracked down a green tinted, NOS, Gran-Prix bubble shield from the 70's.
Lowbrow Customs had a hand full a while back, and Wrenchmonkees seems to have a few in other colors, but the green tint has been quite tricky to locate.
The one below, I sourced from an online shop called El Boneshaker, based in New Zealand.
They've got a few other bubble shields available and are willing to ship worldwide.
Don't expect to find a green tinted one there anymore though. I bought the last one!