Chargeable NiMH batteries for Canon A530

I am a newcomer to the digital camera world, having recently bought my
first digital camera, a Canon PowerShot A530. I would like to switch
from using disposable AA batteries to using rechargeable NiMH
batteries, which are allowable with my camera. I can buy the Canon
charger and set of four NiMH batteries that are made for Canon cameras
such as mine. However, the product, including shipping, costs at least
$44 on the web.

Should I purchase the Canon product, or can I purchase any ol' NiMH
batteries/charger set? If I purchase a non-Canon product, will it work
as well with my camera?

I assume that I can get such products at Wal-Mart, etc. for less than
what I'd have to pay for the Canon set.

Any advice would be greatly appreciated. Thanks in advance.