I hope you told the person who shipped the amplifier that way he destroyed the tube(s) through his carelessness. While one tube is broken, the other could be damaged internally. Tell him in a nice way he made a gross mistake, but be sure to tell him so he learns some common sense in packing and shipping. You have my permission to tell him someone in the business for 35 years says he is "a fool and should pay for new tubes for you". I almost never find a 3-500Z that lives when shipped in the socket. Duh.