Newegg offers the Western Digital Blue M.2 2280 1TB SATA Internal SSD for $299.99. Coupon code "AFM17WD01" cuts its to $284.99. Plus, free shipping applies. It features read speeds of up to 545MB/s and write speeds of up to 525MB/s. Deal ends June 30.
Note: Check the specs to be sure this hard drive will fit your system. It's a M.2 2280 form factor designed for certain smaller and thinner computers.