I used to know tool and die makers that did that back in the day. Sadly, a lot of manufacturing was sent off to China. I assume there are Chinese people doing similar things.
There is a solution to so many problems here (creating usually unavailable parts for machines/devices/products) but the problem is knowing which parts are in demand and currently have no supplier.
A maker would need to have an interest or hobby in such a device & discover a need for the item for it to come into fruition. But just think of how many general 3D printed parts could be printed as solutions for so many products out there that are going unmade.
I was not commenting on the quality of the work. BTE, saying the Chinese quality must be automatically shite is a ridiculous idea.