Just get some Home Depot chicken wire or other readily available perforated metal. More importantly is how you reinforce the mounting points, thats where you'll need to be creative. Also, how are you gonna secure the seat cover to the thin fiberglass??
If it can be made out of fiberglass then it can also be made out of 24 gauge sheet metal, pounded, bent and mig welded into shape. Youll need a good donor to get it right. Maybe I'll start making them......
All our government does is distract us while they steal from us, misspend our tax $ and ruin our country