There is also a guy on ebay that sells it by the sq. foot w/ free shipping to the 48 states. Will cut to your dimension (just rounds it up to the next sq foot).
Price depends on thickness. 3/4" = $14/sq. ft, 1/2" = $10/sq. ft
Still not CHEAP but way cheaper than retail. Just bought 3 sq ft the other day to redo my rod holders in the gunwale.
Link to his 3/4" page:
http://cgi.ebay.com/3-4-WHITE-OR-BLA...item45f09d894b