we just shipped our bikes from Ushuaia to Europe in a Container. No idea what it may cost to US but the shipping agent of Hamburg-Sued probably can tell:
Agencia Maritima Bernard
Gobernador Godoy 36, Piso 3, Of 15
phone +54 2901 423 334
A friend checked flight options from Rio Grande and was told 1.400 US$ to Buenos Aires for the bike and himself.