What value for these Infinite Slope 1.8 speakers?

Three years ago I purchased a beautiful set of Infinite Slope 1.8 speakers and they sounded fantastic. Upon doing some research into the speakers I discovered that one of the designers, John Sollecito of John Sollecito Engineering lived in Connecticut, not far from my home town of Guilford, CT. I called John and spoke with him about the speakers and he had nothing but positive things to say, perhaps as one might suspect but still, these speakers were obviously something pretty nice. I made arrangements with John to bring the speakers in for evaluation and after a lot of discussion, even though he was quick to say that they needed very little work, I decided to have all of the drivers and the crossovers replaced and brought up to 2011 specs. John did the work himself and the speakers ended up sounding far better than I had imagined they might. But these days I am in a downsizing mode and am considering selling these speakers. When John finished the job he stated that if he were to design and sell these speakers today in the configuration that they are currently in, he would charge a minimum of $5500 per pair.

So my question to this forum is about setting a fair market price for these speakers. Would anyone care to chime in on this? I sure could use some constructive help with setting a price that reflects the actual quality of the sound, the beauty of the build and the rareness of the speakers pair in an updated configuration. Thank you ~ Frank Blackwell