Amazon offers the Samsung X5 500GB Thunderbolt 3 External SSD for $249.99 with free shipping. (Samsung and B&H Photo Video have it for the same.) That's $50 under last month's mention and the best price we could find by $80. It features read speeds of up to 2,800MB/s.

Update: The price has dropped to $247.99 at Amazon and B&H Photo Video.