ZyXEL PLA4215KIT 500Mbps Powerline Gigabit Ethernet Adapter (Pair) for $74.99.  Shipping is $5.00 for a total of $79.99 shipped.  Here is a screenshot for your reference.  The set comes in a pair and uses gigabit Ethernet to achieve up to 500mbps transfer speed. Most places have the Gigabit Ethernet adapter for about $99.