For sale is a Zyxel NSA325 V2 NAS including 2x 500GB Seagate Video HDD's. I have owned since new and it's in full working order. It had an easy life storing my digital music albums and running squeeze server for use with Squeezebox music players.
eBay
This is a 12V fixed-voltage MyVolts-branded power supply adaptor designed to meet exactly the power specification of your ZyXEL NSA325 v2 External hard drive.
eBay