Don't listen to him! How do you seriously expect to get a muskie into a BECKMAN NET (make sure to ask the lodge if they have GOOD nets, you'd be surprised) if you cant manipulate its body in there yourself? Most of the fish swim away anyways, its just a little poke. But NEVER gaff around the gills, that's just plain unsporting.
I bought my gaff through Cabelas, just look in the saltwater section. I opted for the 4'' hook, with a 4' handle, but if I had to do it again, I would go for the one with the 5' handle to get even the most cautious figure 8'ers who know to stay back a bit (haha got those gals once or twice before). I usually get my figure 8'ers on the larger believers in Jailbird colour, although if the water is still going to be cold, go for the smaller size and possibly a more neutral colour. Also, you cant go wrong with Mepps 5's in natural for those cold front days, and even a Mepps 3 if you're feeling enough confidence to throw such a small lure. And yes, combined I've probably caught and seen well over 45-60 36-48'' muskies caught on #3's alone in a season.
Also another thing you can try doing is calling your lodge and asking them for detailed lure names, sizes, and colours. Or if they cant give you good info, try a couple of the lodges around there and telling them that you are considering them and have it about 95% talked over with the wife, and now you just need a lure shopping list for the meanwhile. That way they'll give out last years top producers unknowingly and honestly, and you might also be trying out new things on the water you're going to, its a win-win.