Some recent social game developer auctions on eBay:

Early Intervention Games : Fun, Joyful Ways to Develop Social and Motor...

$15.83
End Date: Saturday Nov-11-2017 16:06:34 PST
Buy It Now for only: $15.83
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Early Intervention Games: Fun, Joyful Ways to Develop Social and Motor Skills in
$13.89
End Date: Sunday Nov-12-2017 10:05:31 PST
Buy It Now for only: $13.89
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Social Development Skills Board Game Kids Children Fun Learn Play Activity Gift
$28.48
End Date: Friday Nov-17-2017 12:00:07 PST
Buy It Now for only: $28.48
Buy It Now | Add to watch list