If you feel you can't live without the sound of vintage JBL L100 Centurys, take a look at Craigslist. You'll find everything from original condition to restored. My guess is that they will sound closer than anything else. But my best advice is to audition some of the newer designs at about the same price range as the JBLs. If you're still not satisfied, look around for used early JBL systems, like the 001 or S7s. The L100s will pale in comparison.
Recapturing the JBL L100 Century
Back in the day, teenager in the '70s, the speaker I really wanted but couldn't hope to afford was the JBL L100 Century. Is there a modern day speaker that captures what the JBL did? It would be fun to assemble a modern/retro system that did what say a Dual 1229 or Thorens table, Marantz receiver, and the JBLs did. It sure was a fun speaker to listen to.