Pr6
The problem is that you are not going to be able to sell it because there are no viable end users.
It is not valuable to you unless you maintain that PR, and that means you have to develop, but what exactly do you develop?
If you merely park it, PR will go away fairly quickly. Sometimes you can park and get a burst of activity that brings a bit of income while there's still traffic, but my experience says that revenue tends to be low w/ .org even with traffic.