$400 and you're wondering if you got a deal... You must be kidding

Acetone will removing the oil on the stocks along with out harming the wood. Unforntunately it will remove any finish it touches also. I'm guessing anything that would remove oil will also remove the finish on the stocks. If you don't mind refinishing the stocks it's not a big deal and rather easy to do if you've ever stained or finished wood before. I've done it before and have no formal training what so ever.