Andy - Check the yards around Olympia, should be able to find some marine ply, any decent lumber yard will carry it. If you don't find any locally, Edensaw Woods in Port Townsend or Seattle, Crosscut Woods in Seattle, Flounder Bay in Anacortes. Don't need to go fancy, fir will suffice but, check the prices on the imports. Might be worth it to step up in the long haul if the prices are comparable. You will probably find just 4 x 8 sheets that need to be scarfed together to make the length and possibly the width. 8 to 1 ratio is standard and can easily be cut with a sharp hand plane or belt sander.

West Marine, Fisheries Supply/Crows Nest, Boater's World, Motor Boat Mart. These stores should carry the Gougeon Brothers West Systems epoxies. Get the 105 resin and 205 hardner, a small pump kit and 403 Microfibers for adhesive fillers. Also get a box of latex gloves, a couple of pint sized poly mixing pots, a mess of tongue depressors, a couple flexible plastic spreaders and a bottle of white vinegar. If you are planning to put the UHMW shoe back on, 4 ounce fiberglass cloth should be sufficent. Fiberlay in Seattle for your glass if you can't find it local. You probably don't need to glass it, but it will keep the plywood from checking and creating problems down the road. 9 oz. or 10 oz. cloth if your going to leave the shoe off and add some 423 Graphite Powder to the final coat for a low-friction coating. You'll need a chaulk tube of brown 3M 5200 Marine Adhesive Sealant to put on the bottom of the ribs and chines before setting the plywood bottom on. Make sure you clean up the excess that squeezes out before it cures. It has a tenatious grip that makes it tough to remove later. Use stainless steel screws. On the chine, instead of a steel strip, how about UHMW strips?

For the rest of the boat, a penetrating epoxy sealer would be helpful in reducing maintenance. Besides providing a excellent base for finishes, EPS creates a barrier in the wood that helps keep moisture from weakening the bond of the varnish or paint. It can be used above and below the waterline. You can encapsulate the whole BD in epoxy resin if you want, but it just adds weight and costs, which I don't feel are necessary in a ribbed boat. EPS is the way to go if you want more protection and less maintenance. If you need more help, just holler. Also, Montana Riverboats has a bulletin board where you can tap into more wooden DB knowledge.

Lets see some pics!