Intel does not include this blower in their spare parts list, so you cannot purchase it from them. If you are still within your (3-year) warranty period, you could have Intel replace the whole KY unit via RMA.
Your other alternative is to attempt to purchase a replacement from a parts dealer. The part number I have is SUNON Maglev MF60140V1-C020-S99. In an internet search, I found two sites that offered it, PcHub.com and DHGate.com.
Hope this helps,