It'd probably be better to just recover your headliner than to get a new board - you're not going to find a clean one easily and the transportation is an issue (for some reason the board is as big as the cabin

).
Just go to a fabric store, you can easily find the fabric (had a foam backing) and buy enough to cover it (measure

). Then remove your headliner board, peel the old liner off and then clean the board (a stiff nylon brush will do well here). After that just spray it down with 3M adhesive (can be foudn at auto parts stores) and put the new headliner in. Trim to fit with about 1/2" overlap at the forward edge, you'll fold this over.
Sequoia