There should be some threads if you search for bow refinishing. It probably depends on how well you want them to match your riser and what it was finished with. You could low tech with wipe on poly on Tru-oil or even spray some spar urethane on them. On the more high tech side you could order commercial bow finish and apply with a spray gun. I don't usually have to finish new limbs - usually just refinishing old limbs but tru-oil has worked well as has spar urethane. You have to avoid some types of spray urethane because they can look milky or yellow. I'm sure there is some guys on here that can steer you away from those.