I would think one of the clear wind deflectors so many of us Roadster owners use would work just fine. The ones sold at http://www.dynamicautoconcepts.com/ mount using just the umbrella holder clips (pull the screws out, remove the clips, insert the wind deflector, replace clips and screws) so you wouldn't need to install anything permanent in your car. You and your dog would still have nice clear views in both directions - although I suspect nose prints would appear on the cargo side pretty quickly!

I know the bulkhead shapes are different but it should do the trick.