Down at the water level a hand held VHF will probably get 1-2 miles maybe better. With an elevated antenae you can get more because line of sight is farther. Along with filing a float plan you should consider renting an epirb if you're going to be off shore a good bit. I've heard that you can rent them instead of purchasing for short periods.

Cheap EPIRBs? When I purchased my first motorcycle I inquired about the price of a helmet. The answer was; what is your head worth! Dam it! Of course I bought the better helmet. (good salesman...)

Good luck, sounds like fun.

Clayton