You can go with some small computer fans, there quiet (25-30 decibels) and low draw. I've seen some that draw 0.1-0.2 amps and best of all there cheap! Looking at eBay (where I spend too much time......) there are some listed for $0.99, and pull/push around 30 CFM.
Disclaimer: I in no way resemble the avatar shown. Furthermore, I in no way have any affiliation to the Trailer Park Boys and more specifically Bubbles!