If you know how to make the lip out of FRP, DO IT! For anyone that knows about this stuff, it can be twisted, bended, folded in half, and IT WON'T CRACK!
It might be a little more expensive, but you can save shipping costs by folding them. Here is a picture of a side skirt being twisted:

Sell these in the factory black like that, and we can either paint them or leave them like that. I say $200 shipped or below would be a good goal.
-Matt