I purchased this power supply when the OEM 300-watt model failed and have been extremely pleased with it.  It runs fairly quietly, but more importantly, it's reliable and reasonably priced.  I bought mine from an online vendor (the same one who sold me the original computer) and paid less than $30, including shipping; it arrived within five days. 

Okia apparently isn't a well-known name to consumers, but I've found this little workhorse to be a far better buy than the name-brand options in big-box stores.  My computer is rarely shut down, so the power supply works hard, and this replacement has never let me down, unlike the OEM model that gave frequent indications it wasn't able to meet my computing needs.

You'd be well-served to purchase this power supply.