From all I've heard and read the Long Mfg. Tru-Cool is the way to go.
http://www.importperformancetrans.com/ is the link to his shop. He probably has everything you might need in stock as well as being a helpful supporting member. Many sizes available for less than $100
http://www.tsscoolers.com/Merchant2/...tore_Code=WGPS other option would be junkyard and find a wrecked Tundra or Sequoia and get the factory one. Supposedly the factory one works very well but the Long is better. Installation should be real quick and easy and it's a guaranteed insurance policy. The last tranny I had fixed cost me over $2K.