As long as the stock is decent looking and from the pictures it is I would not do anything to it. As for a collectible rifle it would hurt the value and I am a guy that likes to leave things original if at all possible.
I don't know if it makes a difference to you but you might want to check with Tom and see if that's an original Mannlicher Schoenauer hood or a reproduction, I know a few years ago he was talking about have some made. It would still look better even if it is a reproduction.