I found the firm that made these in China, it was right at the start of Covid and they wanted to prioritise their scaled back production for their existing customers, like Shark and Vax. Buying the MOQ was no problem, but it isn't something I've chased since for several reasons.
Firstly, we are not well up enough on Shark to know which models have which motor in. Parts for cheap machines cause floods of questions on compatibility. And not all Shark motors are the same as far as I know. This will cause floods of returns as people will just buy "a Shark motor" without comparing the old one first. Then, as they're hard-wired in, this will cause floods of returns from amateur fitters who cant join two bits of wire together.
With some parts, it's not just a case of can we get it or can we make it, you've to look at the bigger picture in the context of the general demographic that owns the machines, and the likely customer. We are not interested in selling parts that have a high return rate, and my spidey senses tell me Shark motors might carry a 10-20% return rate. That added to the selling costs and fraud (items not received, returning their old part, etc) would make it an expensive part.