Hey Guys,
I'm not sure if you are still wondering about this - it seems like the post is pretty old. But, in case someone else runs across the question, I thought I would Chime in. I've been in the car business for 20 years, and always try to help when it comes to finding those hard-to-find parts for people that return their leases. Headphones are one of those things that people just dont think about until they have to return their leased car. Then, all-of-a-sudden it becomes an added lease return expense. it's a bit frustrating. While good dealerships will accept factory replacement parts (like IR headphones from china), many dealers want to be able to re-sell their investment with the original parts in the car. ebay is a good place to find parts, but you can also search on Google for reputable companies. I use http://www.froogle.com to find lots of parts sold by reputable companies with good return policies. For Lexus headphones and GPS discs, I have been fairly successful with http://www.audiovideo2go.com/categories/Automotive-Headphones/Lexus/
Just my two cents...
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