Here is what Ed Fowler says about taking care of your knives in the absence of oil..
Care of these knives is simple; the sheep horn in your handle has been carefully processed and aged in my drying sheds. The environment you live in will be different than mine; the sheep horn may shrink even more. All you need to do is apply a little natural oil to the handle, extra virgin olive oil or lanolin or Tree Wax or any natural wax that does not contain silicone is good enough. You can even use the natural oil many of us have behind our ears or on the side of your nose. Just rub your finger behind your ear and rub it on the handle. If you use the knife a lot the horn will absorb enough oil from your hands.
Any oil will keep rust from the blade, many times I simply apply the oil from the side of my nose or from behind my ear just like I suggested for the handle. Any brass polish will work on the guard. When the edge needs touching up, a few strokes on a smooth steel will bring the edge back to life. When you need to use a stone, I recommend a Norton Fine India stone. Again it will only take a few strokes to bring the edge back to an efficient cutting instrument
