I have a big truck intercooler. Its nice because it has mounting points already and should be easy to install. $125 shipped.
Pics..
http://i158.photobucket.com/albums/t97/biggrgivens/truck%20NPR/nprintercooler.jpg
http://i158.photobucket.com/albums/t97/biggrgivens/truck%20NPR/nproutlet.jpg
Dimensions.
20"high X 30"wide X 2.5" thick
It has 27 cooling rows
Inlet and Outlet are 3"