We have a 1987 3207 and the upper helm storage box/bench seat is starting to rot out. The hinged lid has nothing to screw into anymore. The original box appears to be made of some kind of melamine coated board with teak? covering the corner joints. I'd like to use some kind of man made material to rebuild the box, strong enough to sit two adults on and with enough mass to hold screws for the hinged lid. Any suggestions?