Yup, the dealer. You may want to check local junk yards, maybe they have one in good enough shape, it would be cheaper. I called Toyota a few months ago and priced one out (i need one as well).. it was somewhere between $200 - $300
EBAY!!! i needed one and got one on ebay for $15! great deal but the guy was from Canada and the shipping was like $80, but I didn't pay for it so i didnt car.
I found one aftermarket style on horsepowerfreaks.com but they were expensive as hell so i figured i would just go with the oem style which is fine with me.