A friend of mine reached out to someone about the Poly intakes recently, it looks like there's a pause - or worse - in the Poly intake production.
https://cpwebstore.com/Poly
The other big issue is
demand for a lot of this stuff. Every year there's another A body too far rusted to turn into a race car, let alone restore. This hobby isn't getting any younger. It's hard for domestic companies to do a small foundry run and have the product affordable.