If you just want to receive weather broadcasts, there are lots of cheap receivers that will do the job. This one would work fine, especially if you add an external antenna...
http://tinyurl.com/nqx5dr8
If you want to talk with boats nearby (less than 50 miles or so) then VHF will do the trick. If you want to talk to people that are a long distance away then that is where a marine SSB or ham radio come into play. So, it's really a question of what you want to do with it.