I spoke with Camskill on the 24th January. The rears weren't then in stock, but I was told that Dunlop's are only made in small batches and they go to Nissan first. They didn't know when the next supply of rears were to arrive. All orders have to be done online, not phone, so I will need to just order them.
I checked again on the 31st January, found them (front and rear) listed as in stock, and ordered them.
I am due delivery shortly but I've certainly been led to believe these are the correct tyres.
Watch this space.