It appears that the best place to get a replacement is DigiKey, mostly on grounds that nobody else seems to sell this sort of thing. They prefer not to sell small quantities of stuff, though, and thus attach a $5 "handling charge" to any orders under $25. (The fan is $10.)
Clearly, this implies that I should come up with $15 or so of Useful Electronic Bits to add to my order. And thus I get around to the point of this post: Do any of you have any suggestions for Useful Electronic Bits that I can't live without?
(For that matter, if anyone local wants to split an order and save on shipping costs, I'd be glad to work something out with that.)