The retailers for some of those prices are adding up slowly as users give me more info on where to buy some of this stuff. Papst is a really rare one to find i found a german site that has the 80mm@19/26.5 model and the 92mm@23/36, i might order from them and get 10 of each of these 2 along with some other cool stuff i haven't seen like a rubber gasket for papst fans(anti vibiration) and a Black anodized alluminum mesh filter. Tail em and resale some here.
About modifing you heatsink to use a 80mm fan from a 60mm efficently. Depends on the heatsink if this is an alpha/hedgehog type fan, since these rigs suck from hs ya need to create some kinda funnel adapter, over at
overclockers.com i saw a while back someone rigged one up using sheet metal very nice, that i think you can actully buy. Mine is made of lexan and is clear and not as far from the HS so more efficent.
With a FOP38/FDP32 its very simple just attach a 80mm fan grill have the fan clips (FDP32 has to be screwed in no fan clips like newer GW models) grab on that... screw in the 80mm fan to the 80mm grill, and then vola...ya can also go further adding a skirt that will point the excess air that might be pouring over the HS cause of the larger fan and direct it in...i did that also with clear lexan.
Then ya can go improving the conductivy of the HS unit by adding a copper or silver plate under the HS, and then get a high tension HS clip like a alpha clip. Then ya ya got yourself one really badass heatsink!

I'll be posting a step by step with pictures how i did this in a few weeks.
Thanks for all the great comments about my site