You can keep your eyes on Astromart or Astrobuysell as they pop up once in a while.  There was one just recently posted on Astromart but the sale is now pending.
https://astromart.com/classifieds/astromart-classifieds/mounts-equatorial/show/gtocp3-with-y-cable-and-power-supply

You can also post a "Wanted" ad on Astromart and/or Astrobuysell.  That has helped people look for mounts and parts that others have lying around but not considered listing.
Cheers!
Christopher