The dealership...or Sometimes you can call the different tire places around and find some take-offs from someone who bought new wheels. Wheels andcaps.com has them. A few other places online have them as well but they aren't cheap. Toyota recycle yards? Craigslist or the forums. That's all I've got for ya. You might have decent luck going one at a time from the forums or Craigslist if you have the patience...and want the best price.
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