Some recent serious games auctions on eBay:

Serious Games 1st ed. 2017

$96.87
End Date: Thursday Dec-14-2017 18:16:01 PST
Buy It Now for only: $96.87
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Serious Games: Third Joint International Conference, JCSG 2017, Valencia, Spain,
$101.63
End Date: Wednesday Dec-13-2017 18:34:36 PST
Buy It Now for only: $101.63
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Serious Games for Healthcare : Applications and Implications (2012, Hardcover)
$245.00
End Date: Sunday Dec-10-2017 7:36:05 PST
Buy It Now for only: $245.00
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