Eight and a half months ago, I was gifted this Northwoods stockman with carbon blades. In the time I've had it, it has been used a fishing knife, including time spent down on the Chesapeake Bay which is a salt water environment. It's been carried as my EDC pocket knife, sliced fruit, cut down cardboard boxes, and has been rinsed off in a creek when camping.
The only real care it gets is being wiped down with a dry bandana after use. Once in a while I smear some Chapstick around on the blade for time when we were kayaking and it was a wet trip. It survived b ring in the pocket of my wet shorts for the duration of the trip just fine. The blades have darkened, but thats normal for a carbon bladed knife. It's called patina, and it actually helps protect the blade. I would not store the knife in a sheath, that will do more harm to the blade than water. The acids in the leather will rust a knife.
Contrary to what some people believe, carbon steel is not going to rust away on you with just a tiny tad of care. Just use the heck out of it. The Vikings crossed the Atlantic ocean in open boats and the Roman legionaries marched all over the known world in all kinds of weather. They managed to keep their carbon blades from rusting under much more primitive conditions that we live in now in the 21st century. JUst use it, don't worry. Just smear some Chapstick on it when you wipe it down with w dry cloth.
As for the wood, a little linseed oil, or mineral oil, or furniture oil of some eking will be fine. A little on a cloth and rub down for a bit. I've used linseed on the stockman scales, and they've held up fine, even to salt water and fish guts.
