I have not had too much problem with my radios near the ocean. Keep them out of the sand and salt spary and tey seem to be fine.
I did drop my Zagi wing into the Long Island Sound one time. I got it out of the water, brought it back to the car, and cut it open so I could get to the electronics. I poured two bottles of fresh water over everything.
I pulled everything out, cleaned it out with fresh water. I took the cover off the receiver and flushed it with water, then alcohol.
Only loss was the receiver battery. Salt water shorts the battery out so that had to go, but every thing else was fine. I let it all air dry for two days. Then I tested and put it all back. Still flying 5 years later.