I've got a friend looking to sell his amp supply LK550, three tube 3-500Z amplifier. 160-10, for the unaware. Instant on, full power. This is an extrememly clean unit, with low hours on the tubes. He's been inactive for the past 10 years or so, and the unit has been packed in storage. Would anyone care to venture a guess as to the fair market value? Jim/n2ea