help,, what parts needed for 2 screens

i have a pioneer deh-p7300 deck and i want to hook up 2 screens in each head rest but i dont know for sure what the rest of the parts that i need,,,, i know i need some source for video i.e. vcr, dvd,ps2, or tv tuner, but i want to know what else do i need and what cables do i need to make the stuff compatible with my deck,,i dont think i am going to get all pioneer stuff (to expensive),, peace