I made a fenderboard out of 2" schedule 40 PVC pipe. The pipe is actually about 3" OD, very thick, sturdy, and stiff. I bought a 10' length and cut it into two pieces and made two of them like this:
This is not any less expensive than a real wood fender board, but it assembles/disassembles and stores more easily. Since my cockpit lockers are all <5' long, I need to store it inside my cabin. I only like having clean stuff down there, and the PVC wipes clean a lot more easily than wood.
I only use these a few times a year when visiting Chesapeake marinas that have non-floating bulkheads with pilings, requiring me to have fender boards to keep my boat from getting bashed up. On the Delaware River everything is floating docks, for which I have teardrop-shaped fenders that work better for those but don't work at all against pilings.
I use this with 6.5"x23" fenders, so with the PVC pipe it holds the pilings about 9" away from my hull, so the rubrail and fragile hull-deck joint do not come close to the piling. A well-placed knot on each fender line and a couple wraps around the top of the fenders keep the pipe at the perfect location between the fenders. It all disassembles very fast for easy storage under the cabin settee.
The fender and pipe sizes work well for my 25' boat. Dimensions could be upsized for bigger boats.
Not sure I would trust PVC in a heavy storm, though. But not sure I'd trust a 2x10 board under those conditions either.