Not sure why it's delimited to "Adcom or Parasound." With $4k as the top limit, there are some very good options out there.
https://www.usaudiomart.com/search.php?show_other_marts=N&keywords=&search=Search&type=F...
https://www.usaudiomart.com/search.php?show_other_marts=N&keywords=&search=Search&type=F...