Just noticed after navigating away from the 8tb drives I just bought that the WD Red 10tb are on sale for 215.99 for Prime members as a Deal of the Day. Will be back in stock July 29, but looks like you can order them now.
https://www.amazon.com/gp/product…=UTF8
IN STOCK AUG 1st
Edit: newegg has the same deal:
https://www.newegg.com/p/N82E1682…lsrc
and BH Photo has a retail kit: https://www.bhphotovide