I bought a pair of waterproof walkie talkies from Bass Pro Shops and use them for talking to my friends while fishing while still reserving the VHF for other things.
Here's a link to the one that I bought a year or so ago. So far I've not had any issues with them and yes, they are waterproof and they float. Good thing too, as I dropped one of them into the drink the first time out with it.
http://www.basspro.com/Motorola-Talk...SSSELL_PRODUCT