Easy fix - some sellers on Amazon (new of course) have them for around $90 thats where I picked mine up.
The links:
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And if you want to save money, just get the MDR-V6 for $20 or so less. The only downsides are a nickel plug instead of gold plated, and the lower availability of spare parts (since it's not a "professional" model). Of course, these things are durable enough that I doubt you'll need them. For what it's worth, I have the MDR-7506, but that's because I needed the headphones NOW when I bought them, and the only place locally was guitar center, which only carries "pro" (hahahahahahah) stuff.