With the pinout posted on this blog, see here
It is possible that you create your own composite AV cable, as the sales of these things is very tricky. Pineriver is finally sending them out of the door, but in very limited supply.
I’m still waiting for one to arrive, hopefully that is very soon.
Akrim posted on this blog a link to his own cable, which he managed to create from a normal plug that is too short. Cut the plastic, file the plug and you’re done. Many thanks for this AK.
Image is clickable