Thanks everyone for the input!

I won't be using the ka-bar on the water. It will be safe and dry inside a drybag when I'm on the water. I also got the knife with a synthetic handle, so it shouldn't disintegrate. I will want to replace the leather sheath though! I consider batoning an essential use for this knife - the mora looked a bit too thin for me to want to abuse it like that.

I'll try and track down some thin plastic sheeting - the tarp I saw at Cabela's was very for its size. I've thought about adding a ferronium rod too - I have one, but haven't used it enough to be able to consistently get a fire going with it. More practice!