Acetone should do alright...do it outside if possible since it is fairly flammible and evaporates fairly fast also...find a container which can be closed up to prevent evaporation, while allowing full immersion and let it soak a while, a week even, and wick out the Oils.
Kerosene might do well also, if possibly benifiting from being kept warm for the prolongued soaking.
Or, Kerosene, and, after a long soak, then Acetone.
Should do it...and, these Solvents are inexpensive and easy to get anywhere there's a Hardware Store.
Keep them off of your skin of course, same as any solvents, just on principle, and as kindness to your Liver.