I just received a P3 camera yesterday for possible repair. Having never seen one before, I was curious as to any possible similarities to the P2V+ camera/gimbal unit. Sadly, there are none. The P3 camera gimbal looks the same, but is dimensionally different, all around. DJI thinks they came up with a better camera/gimbal unit, but all they did was come up with better video quality. This unit is heavier, an attempt to make it more robust, but all it did is amplify the same damage you get when you crash a P2V+. The pitch motor still separates from its bracket and the ribbon still tears. BTW, the ribbon is TOTALLY different, as it splits into a "Y" configuration, going into 2 connectors on the main circuit board. I like the small fan above the main board, and the "heat sink" design of the upper main board body. DJI's attempt to diffuse the heat coming from the main circuit board.
So, it seems like it will be awhile before anybody starts offering ribbon cables, and parts, in general will only be available the way we get P2V+ parts today. From buying up damaged cameras.
Fly safe, don't crash.