Newegg.com has 450W EVGA 450 BV 80+ Bronze Power Supply (100-BV-0450-K1) on sale for $19.99. Shipping is free.
Quiet and Intelligent Auto Fan for near-silent operation
80 PLUS Bronze certified, with 85% efficiency or higher under typical loads
Fan Size / Bearing: 120mm Sleeve Bearing
Heavy-duty protections
ATX12V / EPS12V