We do all of it our self. It is a high temp silicone powder not ceramic. Much like 2618 alloy pistons with their higher silicone content which allows them to handle heat and detonation better. The ceramic powder has less flexibility and is more prone to fading and chipping overtime even though it has a slightly higher temp rating.
I was perusing your website and I saw you make your hot side from 304 stainless. Everything I've read says that 304 will heat harden and crack in turbo usage. How do you combat this?