Upload & Sell: Off
Are you an experience diver? Only reason I ask is the camera gear / getting good pictures really pushes your bouncy control / comfort in the water depending on the conditions. A P&S w/ single strobe is a lot easier to manage than a full on dslr kit (when entering the water, during the dive, etc). However, with a d800e you will be able to build a really nice system. Keep in mind you will have spent more on underwater gear than your camera by the time it is all set up.
If I was buying another underwater system it would be a used ikelite t2i housing w/ dome and a tam 10-17 fish lens. Match a couple nice used strobes like the 125's and get wet. If the camera gets flooded just toss it and buy another $250 body...
Try wetpixel.com for more good information.