That should be easy enough. Dive watch technology is pretty well developed these days.
One good candidate would be the Freestyle Turbo ($70; www.freestyleusa.com), a solid, simple analog-style watch, rated to 660 feet (as if!), with phosphorescent hands and stainless-steel buckles. Nothin’ fancy, but reliable and easy to read. It’s available with a blue or black face. For something a little more tech-y, check out the Invicta Pro ($130). It uses solar energy to recharge its battery, and can run for two or three days without a fresh boost of light. It’s rated to 600 feet, too, so no worries about having it implode if you get down to the triple-digit depths.
Still, my temptation would be to go for a really nice dive watch, such as a Citizen Aqualand Duplex ($300). After all, it includes a digital depth gauge as well as the usual watch functions, so it’s a two-for-one proposition. It even measures water temperature and logs maximum depth for up to four dives to help calculate decompression requirements. Plus, Citizen dive watches just reek of Jacques Cousteau chic. They’re simply beautiful to look at, as well as extremely functional.