Value of a Proceed HPA3

I have an extra Proceed HPA-3 in my system.  Any idea of what these are going for these days?  It has been serviced at Pyramid about two years ago.  Nothing broke, just regular maintennance.  Cosmetically is great shape!

Thanks for all of your advice!

This question is from almost a year ago.
What happened to your Proceed HPA3?
Do you still have them?
yes, I still have the Proceed HPA3.
the Proceed HPA3 is in great shape.  It is currently used to drive a center and surrounds.