Crucial X9 2TB USB 3.2 external SSD - $99.99 (69.99 with account) (Microcenter, shippable)
SK hynix Tube T31 Portable SSD with DRAM 1TB (42mm SSD in a portable casing) $61.99, Prime Members
SK hynix Tube T31 Portable SSD with DRAM 1TB (USB drive-ish) - $69.99