Best speakers circa 77-79'

I'm putting together a "vintage system" to play my old vinyl, and I wanted to find out some recommendations on speakers. My old set of B&W's died a few years back, and my Yamaha NS-20m's are frankensteined with new parts etc. I was considering JBL 4311's or Infinity (I'm not sure which models are best). Any help?? I'd like to stay in the 1976-1979 range (and also the less than $300 range if possible). My records are mostly pop/rock with some jazz and a little classical. My set-up now is a Yamaha 2020 receiver with a B&O turntable. Thanks so much for any information!!

Doug