I recently took my first go at splitting some staves, and I have to say it is a real pain in the butt! But also rewarding. I would say that if you want to get really good staves then saw them for sure, but if you want to be more traditional then the question is moot. (You should be splitting them if you want to be trad.)
I don't know how well this will work, perhaps someone else could comment, but I used some paint we had laying around from painting the house. I just dipped the end right in the paint a couple of inches, let it drip off, and boom, sealed end. I think that you could get some mismatched paints about anywhere pretty cheap. I have also heard of people using polyurethane.