Explains the dilemma pretty well now. The problem being, that nobody caters to the orientation requirements that you want, although what you ask is reasonable.
Apparently lots of people have this issue (as a quick google search indicated). I was unable to find an inverted Planisphere but I am sure you already did your research on the internet as well...
Any chance you can sacrifice your Planisphere, make a mirror copy of it, have it laminated and then "assemble" it back?