New poster here, long time lurker..
I've called about, and inspected several (9 iirc) different cnc converted mills in the Dallas/Fort Worth area in the last 6 months, and am pretty confident your setup would sell in a few days @ $3000, and within no more than a few weeks @ $4000.
If you were willing to wait something like 2-6 months I believe you might be able to get in the $4500-5k range - but that's iffy, imho, as most people willing to spend $5k, as others have said, have a LOT of other options available to them.
Wish you were closer, but +-1500 miles is way too far for a tool run for me.
If I were you, I'd advertise it @ $4500 obo on craigslist and see how many responses you get in the first 2 weeks. If no one wants to come see it in person within 2 weeks, drop it to $4000 obo and go from there...