As of January 2019, desktop hard disk drives typically had a capacity of 1 to 6 terabytes, with the largest-capacity drives reaching 15 terabytes. Unit production peaked in 2010 at about 650 million units and has been in a slow decline since then.
You can now buy new or refurbished Dell 300GB 10K RPM 3.5inch USCSI Hard Disk 0D5796 at best price in Nigeria.