Would it be possible to get a picture of the reverse with the straps out of the way so we can see if the pins are stuck through the back? Not that this is a yes or no sign of anything, but it can be helpful in an overall assessment.
My first impression is that this is a fantasy piece. One has to be very careful these days regarding officer's boards, as you can purchase reproductions of nearly any cypher or other Auflage that was made. Once they are stuck on a board, it is very hard to tell if they are period pieces or not. The fact that this pair is unworn/unused is worrisome, because there are so many unused tailor shop boards still floating around that have nothing on them and as a collector's item are fairly worthless....that is, until you add some embellishment.
The next flag is the yellow underlay. I've never seen a medical board with anything but black, blue/black, dark blue or a purplish blue backing. The backing was also to be a velvet like material. The rank of Oberstabsarzt, which this is supposed to be portraying, is supposed to have a black cord intertwined with the silver cords for Prussia. It's not there. Finally, the combination of crown and Äskulapstab is something that I have never seen and I doubt existed. What would it be? There were only a handful of cyphered regiments that used his crown. None of them had anything other than a royal cypher below them on a shoulder board.
Regards,
Chip