Steve-I have called all those companies on numerous occasions requesting shock for my 960-Koni at one time offered the parts for the rear and now have discontinued the part-with that being said they do have one single shock in stock, not two ,just one,-have been able to locate shops overseas that have leftover stock-but your looking at a cost that is outside the norm for gold, plus shipping from overseas.
The shocks that are one the back of my ride now are the Monroe Sensa tracks-there not Koni or the rest but they are the best thing thats been on the car to date-there good enough that I'm springing for the front struts also-wish I had one of the brands you have mentioned above, would be fun to know just how well these cars can really handle.
Poolman