As rare as hen's teeth, unfortunately. Our market is too small to support a decent level of refurbs.
I am still kicking myself for not buying one at the time - my 2009 was still the ant's pants back then.
I checked another store this morning and found this one. It is a base mode 2012 i5 with 4GB and a spinner for 100% of the original list price (?). These folks are in Tampa, Florida. Has anyone used them before?
http://www.macofalltrades.com/Refurbished-Used-Apple-Mac-Minis-s/299.htm