Vintage speakers from the 70's and 80's

Slant 6 Apogee.

if you are running a marantz 2270, as do i, i suggest a pair of marantz imperial IIX speaker system -but good luck finding one.

before i found those i was running it with some polk a-10s. lots of sonic depth and clarity. good luck on your quest!

There are several great speakers from those two decades, but I'd go for something iconic.
If you want an "ultimate '70s system" AR3s, or AR1Ws with Janzen tweeters... maybe just a pair of Janzen two ways. Allison 1,2,or3s, or Dahlquist DQ10s,or 20s would also be excellent. For an early '80s system, I'd go with Ohm Walsh (any from 1-4), or maybe AR9s... but 9s really need a bit more amp. If you want to add a turntable, I'd go Thorens for the '70s, or Rega P3 for the '80s.
Cliff

Many great suggestions here. If you are looking for monitors I would also throw in the Fried Beta or Beta Signature and any version of the Fried model C.

ah, Dynaco A25. My very first set of "audiophile" speakers bought new in 1972. My friends with Cerwin Vega wondered what I was thinking. Where was that booming bass?

Then they learned about music as opposed to sound.

Then went on to Kef and PSB