Glastron Speed Boat

Chances are they were originally made with good old plywood for exterior use - glues are water resistant. Use galvanized fasteners bronze, or silicon, if you want them to last long. Monel staples are made from alloy steel and can be found at Home Depot and others ..

Hey I consider buying new seats in a big boat stores, they are not expensive and often have structures rotomold theres nothing to rust. If you are determined to make yourself, try to use regular-grade plywood CDX but sealing them with epoxy, or at least one poly resin.

You must use the seats. Seriously marine grade plywood is fine, that's what they are made of, but you can buy replacement tickets for essentially the same business that you will build them, so why bother, unless you want something custom, which is good. If so, you can always buy the upper portion of the seat fairly cheap.