expect they cost him more. BUT if this is going into production as it has. He should have gone to an overseas source and had the cast iron parts made. Then machined them in the US.
Dare I say, Use China for what its good for. Making cheap parts. Even if half of them are rubbish they would still be a fraction of getting them cast in the USA.
This gets back to my first point. Sell them for $500 and he could have moved a container of them easily. Made them cheaper, not had supply problems, and NOT had copies threatening his market.