Updated Apr 23/19
OWC Mercury Elite Pro Quad RAID 5 USB-C Enclosure -
$439 - more in soon
High quality 4 bay hard drive enclosure, with USB-C connector, that comes with SoftRAID, so you can do RAID 0, 1 or 5. The removable drive bays can take either 3.5" Desktop SATA drives, or 2.5" Notebook drives or 2.5" SSDs. Enclosure is in theory capable of doing over 1200 MB/s, depending on the drives and RAID selection. Has a Kensington Lock slot. Warranty - 1 Year with OWC. Comes with USB-C to USB-C Cable and USB-C to USB-A Cab.
Find eSATA cards here