Any ideas who makes this rear wing?
How about this?
Available for an S2 EP Tuning Rear Spoiler | EliseParts
I dont think you are a million miles off there John!
The one in the picture is just higher, I think?
Agreed. I suspect DIY mounts to get it higher.
Is higher proven to be better?
I believe this is more to do with clean airflow. In theory the higher the wing the cleaner the airflow.
I am more into it for internet points TBH, but dont tell anyone 
You know you want to…
I cant get on with how that looks. 