eBay is the only market am aware of.
Prices are very cheap now, yeah. Probably $30 each might be the average?
Or at least, that's where it was about a year or two ago.

Everyone wants a remote with voice-activation now (I don't).

MX990's are tanking in price lately also.
I used to get one or two emails a year from eBay when an MX990 dipped down into my price range.
Now I'm getting an email every week.

Did not know about that 32bit driver issue.
But that's what VM's are for! :)