The foam I use is by creatology, it's your typical craft foam. I got a 36x60 inch roll for like 6 bucks. Glue is your dollar store super glue. Gesso spray is 8 bucks at Walmart. Kryon spray paint is 8 bucks at walmart as well.
I'm cheap and lazy to learn to use fiberglass/resin. This method I think it's really good in my opinion considering the cost and time and skills required. It's a variation on the Japanese Cosplay player using craft foams. I don't think anyone else is using this method. I can post a more detail tutorial/explanation if needed. Thanks for the kind words.