Some recent Streaming Music auctions on eBay:

Sonos Play:3 All-In-One Wireless Music Streaming Speaker (Black)

$76.00 (4 Bids)
End Date: Saturday Jul-21-2018 16:32:17 PDT
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TP LINK HA100 Bluetooth Music Receiver Stream music wirelessly from smartphone
$17.99
End Date: Monday Jul-23-2018 15:23:28 PDT
Buy It Now for only: $17.99
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HP Wireless Audio Music Streaming Kleernet Tri-band Connectivity O5756
$29.99
End Date: Saturday Aug-4-2018 9:34:22 PDT
Buy It Now for only: $29.99
Buy It Now | Add to watch list