That's why I use 6x VMCs
And EC makes a 4x saltwater finish L777 hook. Before VMCs were generally available, it was all I used. The finish holds up much better to corrosion than the VMC Perma-steel does. However, they are as dull as a butter knife out of the box, and they have longer shanks so they may not work as well as VMCs when used with a split ring.
Here you go--L777 trebles with the "Sea Guard" finish. Looks like they still make them. I'm pretty sre they came in sizes up to 5/0:
http://fishlazer.com/products/hooks....yleName=Treble
Threaded Mode