why not buy one of those fake wood planks like they use for decking? They're not exactly cheap, but will last a lifetime as they don't rot and are impervious to termites, weather, etc.
**edit**
I have a piece that's 4.5' x 5", about a half inch thick. You can have it...I'll be in Long Reach on December 5th (Saturday), if you want it I can bring it with me.