@jmarki ... guess I want to walk back by suggestion, being as the speakers and amp are partners, your speakers are already at the level of the amps you have and likely wouldn[t respond to an amp upgrade as much as mine did (I way upgraded my speakers, so way upgrading my amp was called for.).
I use audiogon classifieds, ebay and https://www.usaudiomart.com/ to see what others are getting for the equipement I'm looking to sell.
All the best.