Amazon.com: Western Digital AV-GP WD5000AVDS 500GB 32MB Cache 5400RPM SATA II 3.0Gb/s 3.5 Internal Hard Drive (CCTV DVR, PC, Mac) (Renewed) : Electronics
Amazon.com: Seagate Pipeline HD 500GB 5900RPM 8MB Cache SATA 3.0Gb/s 3.5in Internal Hard Drive - ST3500312CS (for Surveillance System, CCTV DVR) - 3 Year Warranty (Renewed) : Electronics
TiVo Bolt Vox™ (500GB storage) 4-tuner DVR with voice control: records cable TV programs or over-the-air broadcasts, and streams web content at Crutchfield
SEAGATE 500GB SATA INTERNAL DESKTOP PC 3.5" HDD HARD DISK DRIVE CCTV MAC DVR PVR 4016138734935 | eBay
Video Surveillance Hard Drive Disk | Toshiba Hard Drive Disk | Hard Disk Toshiba 500gb - Hard Disk Drive - Aliexpress
MaxDigitalData 500GB 8MB Cache 5900PM SATA 6.0Gb/s 3.5" Surveillance CCTV DVR Hard Drive (MD500GSA859DVR) -
Video Surveillance DVR Hard Drive 500GB
Vivetronic 500GB 8MB Cache 5700PM SATA 3.0Gb/s 3.5" Internal CCTV DVR Hard Drive (TP42232A000500GA) -