[jamesfmilne]

Yes, Tehuti Networks[1], which is used by some Thunderbolt 3 Ethernet adapters, like the Akitio Thunder3 10G [2].

(OK, not quite <$100, but <$200)

[1] http://www.tehutinetworks.net/?t=LV&L1=3&L2=0&L3=0&L7=156 [2] https://www.akitio.com/adapters/thunder3-10g-network-adapter