Someone has to make them, or have them made, before they can be sold. Therein lies the rub.
Hednut did a great job, but its often thankless. Shopping for a machinist, bickering over price, coming out of pocket timewise and money too i think, having confirmed buyers back out on him, etc. Burned out, don't blame him.
But a classified in "parts wanted". I've seen them come up once in a while.