Let me add something. I have worked in retail and wholesale electrons years ago. The industry is still very cost aware. Special OEM designs are just not suitable for mass market distribution. IMO, if a device is important to you, then you have to buy some kind of insurance or warranty extension to protect the investment.
The alternative is to sort through the junk and overstock and surplus dealers until you find a replacement part. In fact, that is what some technicians do and they have to charge for the time they spend finding the spare part. This is true also of other industries. Automotive, Construction, Elevators and industrial control are other areas where finding an original part can be expensive. It is part of the cost of ownership.
You can Google for
Surplus Electronic parts.And find results -
Like This...One of the first on the list...
Alll electronics.You ha e to find it yourself in the catalog and you take responsibility for a good match.
They do not take liability for anything. EDIT: Here is a spec sheet for a cheap fan. You have eto decide if it is even close to what you need.
http://allelcdn.upshotcommerce.com//mas_assets/theme/allelectronics/spec/CF-447U.pdf