I'm sure this was mentioned in a thread late last year as someone was looking for the same stuff.

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http://www.mysandman.com.au/forums/showthread.php/7126-Cargo-area-strut-baffles

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That's a link to the thread I mentioned, and my poor attempt at making a link to it.

Cargo-area-strut-baffles in the search bar may get you to it.