Patsy-

Eric Schade of Shearwater boats makes a hatch next to the cockpit that he calls a "binocular hatch." It has a hinged lid and there is a tray mounted under the deck about (I'm guessing) 6" deep. The lid has a gasket just like your deck hatches do, and it has a knob closure device. He sells the knob closure on his website. I tried to find you a picture of the hatch but I could not find it. He mounts the hatch in front of the cockpit, but you could possibly move it to one side or behind the cockpit and still have room for your deck bag. Hope that helps. Option two: Get a pelican case and lash it to the deck. They don't leak and are easy to open and close.

-Malcolm