A month ago, I ordered one from a local vendor who mostly sells parts for old electronic gaming hardware. They substituted a similar 40mm fan, but the one they gave me didn't include a heat sink, or attach to the old heat sink boat, had fewer blades, and spun in the opposite direction. It was only $15 so I didn't bother to return it. I saw some others online that looked promising, but with a very long (October) lead time. Still looking.