Does he have any 12au7/ecc82/5963? My preamp takes those. Or EL-34, or 7199, which my still in transit old Dynaco ST-70 uses. Maybe a pair of 300b tubes for a home built SET amp.
Old tubes are getting harder to find, but new production in Russia, China, eastern Europe has been taking up the slack. Tubes never really completely went out of use, they were just hidden away in military gear.