Check out, fly-bluesky.com. There are alot of other aviation sites to. The head sets are really confusing because there are so many. I'm going to put them in my Top Gun but probably a project for next winter. Doug

You may also want to look at the unit that Revolution Marine sells. I bought one and installed it myself in my 38 flat deck.
I used 4 ports for the head sets and the unit comes with ports to hook to the marine radio, stereo, cell phone and the alarms on the motors.
I tried using the "boom" mikes, but in a standing position there was too much wind noise, so I'm switching to the throat mikes.
Revolution Marine was extremely helpful in every regard with the system. Give them a call or e-mail.