A couple of things--
1) Consider whether it makes sense to get in the water for these shots. Whether from the beach or pier you can get a better vantage point with a long lens.
1b) If the surfers don't know you, you may not be welcome in the water like this. I grew up near Huntington. I wouldn't go into the better waves with a boogie board (considered a kiddie toy) much less a camera. These were not people who were into sharing. Heck, they were pretty aggressive with other surfers. Can you get out of their way if they catch a wave near you?
2) Nikonos: great camera. Has some major limitations. The only two lenses which work in air are the 35mm and the 85mm (as I recall). Neither particularly long. The Nikonos is a viewfinder camera. It isn't even a rangefinder. You set the focus distance on the lens and aim with the viewfinder. No autofocus. No rangefinder. They are wonderful cameras and dirt cheap these days. But know the limitations.
3) As to the lifetime of a camera by the beach: film bodies are cheap. You can get an N90s for next to nothing, and an F100 in bargain condition for <$150. (I'm putting things in Nikon framing because that's what I know). Depending on your means, consider the body disposable. You are taking a camera off the shelf and putting it to use. Glass might be a different matter. Consider whether you need autofocus. Are your subject essentially at infinity? If so, why worry about AF lenses. Could make for cheaper glass, and, again, the ability to consider the glass disposable.
I don't know Maxim styles, but most of the bodies I see at KEH are dirt cheap. Top of the line is still under $200. Most of the glass (with a couple of notable exceptions) is under $200, and much cheaper than that. If this is the system you know, you could be in for cheap and, then, who cares if this is your beach camera? Save it from collecting dust. Run it into the ground. You'll probably get a few years at least.