I had a TEAC A-3440 multi-track back in the day. Go for Otari or Tandberg - they have a very strong following and are serviceable. Note that head alignment isn't enough - you also have to bias the record circuit for the tape(s) you want to use. I suggest you bias for a tape that is still manufactured. Not sure what's out there anymore.
Good luck & happy listening!
Good luck & happy listening!