Your Forever Pieces? What and Why?

Easy one: The Accuphase E-202 integrated amp I purchased new in 1979 and reconditioned in 2014. Sweet sound, stunning build quality. A classic. I also have the matching T-101 FM tuner that’s equally excellent. I would never sell them!

I'm a headphone guy - love my:Sennheiser HE 60 (Baby Orpheus) with my KGSS AmpAKG K 1000 headphones with my Krell AmpSennheiser HD 800  and  Stax SR 007 mk1

Now don't laugh...my Pioneer SX-1250.  Once you replace all the old electrolytic caps (especially the harsh sounding tantalum ones) it becomes a different beast!

I also still have a pair of LS3/5A clones I built 40 years ago that still sound fantastic!

McIntosh MC275.  (Although I've learned in life to "Never say never!"

I have a MFA Magus B bought in 94. Have upgraded it twice. I use it only for the phonostage now. 
Shout out to Sota turntables. Had a Satelite from 91 to 2005 and traded it for a Nova. Never will let it go. 
Also, have a Koetsu Rosewood from 86.