I don't think there is enough volume for Pentax refurbs.
I'm sure there are returns and the occasional refurb sale, but I don't think there is the heavy manufacturing that exists for other brands. Pentax has never churned out product. It's never been that way.
I think Pentax makes things the old way, in batches, on limited assembly lines.
I would not be surprised if they destroyed returned product much the way Cannondale did with their bicycles.
edit: I remember the day, when my 2nd generation Cannondale Raven (that I was racing on) was recalled by Cannondale. Since I was semi-sponsored, as they were handing me a new Jekyll frame, they took a ball peen hammer and smashed the Raven to bits. I cried a bit seeing that happen.