If blade performance is what you are after, here are the four best I can think of in ascending order:
Microtech Black Marlin. S30V, good heat treat, a bit on the stiff side, only drawback is the handle is metal, which might not go over so well in Alaska (Cold). I think these are in the $80 to $100 range if you shop around. The black coating will look scraggly after a while but will help keep corrosion at bay.
One link to get you started:
http://www.theknifeconnection.com/micblacmarfi.html
Melvin Dunn makes fine, affordable fillet knives from CPM 440V. The Diamondwood (pakkawood) he uses isn't my favorite for looks (but is quite durable and practical), but there are 3 colors that are tolerable (Rosewood, Oak, Earth). He also does micarta... linen micarta bead blasted would look a bit dull but would retain some grip when wet, and would be pretty durable. Or you have him do something else nice that is also durable like Ironwood for an adder (that's what I did). He does 3 sizes, 4.5", 6.5", and 9", $119, $129, $149. He's been heat treating 440V for a good while... and so it should be an abrasion resistant and corrosion resistant fillet knife. Melvin isn't exactly the easiest or most congenial maker to talk to, so don't let that through you off of a good knife.
http://www.dunnknives.com
Bob Dozier has some very nice looking fillet's and he'll do them out of S30V now, but these start at $215 and go up to $275. Dozier's handles are great... and he knows how to heat treat also. D2 might be a bit of trouble around salt water, depending on how well this guy takes care of his knives. I know a lot of the guys I fished with in Louisiana bought $20 knives and treated them like he11... sitting in salt water in the bottom of the boat, etc. Bob is charging a $60 premium for S30V but it should hold up noticeable amount better than D2 corrosion-wise.
www.dozierknives.com
His web site won't come up for me right now... think these are in the "knives for sale" or "Available now" area. Just poke around and you'll find them.
Maybe the best of the best would be from Phil Wilson. He is an expert in making fillet knives and an expert with the CPM steels, so I'd probably choose S30V. He doesn't have a web site... think his knives start at $275 or more though.