found some 8TB lot of 10 for $1000. Still a little too much:
https://www.ebay.com/itm/LOT-of-10-HGST-8TB-7200RPM-3-5-12Gb-SAS-HARD-DRIVE-0F23765-HUH728080AL4200-4KN/223894269019
https://www.ebay.com/itm/LOT-of-10-HGST-8TB-7200RPM-3-5-12Gb-SAS-HARD-DRIVE-0F23765-HUH728080AL4200-4KN/223894269019