Hey guys, was looking around a while ago for some eggcrate I could get in Aus, and came across these guys. One thing I didn't notice at first however, is they actually have a clearance section here: Insulation Industries - Product Catalogue-Clearance- Free and discount items
Just scored a nice 550x740 peice of eggcrate for only $32 to ship it up to me, they have quite a few there. They also produce sheets up to 1220x1220 for a pretty decent price if you need it for a larger machine, or they have no clearance products.
Just thought I'd share