If the organ has not been changed tonally, the Clarinet should be kept and restored. A competent reed voicer will be able to make it stable and milky as clarinets should be. PM me if you would like recommendations....
Reeds keep their pitch(ish) but the flues go with the flow temperature and pitchwise which is why at the moment with the weather as it is, it would be best to avoid any reeds at all!
Peter