...There is no "sealant" of any kind that will stop the salt damage from re-occuring...
Not so fast!
Is it feasible to seal the wood with epoxy in the barrel and action inlet areas? Under the butt pad/plate?
Wax wont last but epoxy is pretty damn impermeable.
This. WEST epoxy will seal it if you strictly follow the formulator's instructions for creating a sufficient vapor barrier.