In order to determine the cfm and rpm you will have to check the psu fan for some sort of identifying data. You'll also have to determine the thickness of the fan. Looking at the photos I would guess it's a generic OEM fan that probably runs at full speed.
jsc - There's only a couple there and I'm not sure they're suitable for a psu.
BTW - off subject - You know those missing internal case speakers you mention? I was at a Fry's Electronics store last weekend and saw two new motherboards with a genuine digital display that was capable of actually displaying the error code. Say goodbye to beeps and a couple of tiny blinking led lights.