Connection port RR armrest - Where to get an iPhone lead?

[YRRunner]

I'm picking up a RR TDV8 Vogue on Friday, used on a 57 plate. Garage wasn't. RR main dealer so had no clue about the comms. Screen says "no telephone installed". Is this because some form of equipment needs to be attached to the port beneath the centre console armrest? That being the case, what kind of lead do I need in order to connect a new iPhone (with the tiny input) to it and where can I get one? Many thanks for replies and advice.

[HowMuchLonger]

Have you tried connecting via bluetooth? PIN number should be in the manual.

[LHD]

Should be 2121 as the pin code if the car has the module fitted.