I had to think about it. Most of my equipment is tube and either built new, or bought new in the last 13 or so years, same for my sources.
I have an old BSR spectrum analyzer I bought in '86. But the oldest is a Realistic TM-1000 tuner, and a pair of Oprimus 2B speakers. It's what left of a Realistic system I bought in '75.
I worked there in high school and bought the tuner, matching SA-1000A intigrated amp, LAB turntable, top loading cassette deck, pair of Optimus 2B speakers, and later that year a pair of Optimus 1B speakers.
The tuner still works great, although it isn't used much and is sitting on a shelf.