Thanks Slabhunter
I do exactly the same thing when I fish the 3.5s for trout. As an old commercial troller, I am not afraid to use larger hooks on salmon.
You can try the sickle hook as long as it is nickel or stainless. Black steel will still work, though most are clear coated and no voltage will come from the hook portion of the lure. Most black nickel are ok.
The swivel will probably have a brass body with nickel coating. They will reduce the voltage slightly at first. I have seen the nickel plating come off after a week or so of voltage reaction. Then more brass is exposed and voltage will reduce even further. This doesn't mean that the fish won't like a lower voltage there. I just want you to know that if the lure doesn't produce, that may be the culprit.
I just got a report from one Alaska commercial troller. He had a few sample anodes to try. After day one, he ordered 4 dozen more. He was just as happy after day two of fishing.