Newegg offers the HGST Deskstar 4TB NAS Serial ATA 6Gb/s Internal Hard Drive, model no. H3IKNAS40003272SN, for $159.99. Coupon code "ESCETFM23" cuts it to $139.99. With free shipping, that's tied with our February mention the lowest total price we could find by $9. This 7200rpm hard drive is designed for NAS systems and features a 64MB cache.

Note that this is the bare drive.