Park assist ECU for 2011 Vouge help!!!

Hi all, I got a 2011 4.4 TD8 RR Vouge & my park assist has totally packed in, as in DEAD, no light on P button, no fuse blown as I got some good info off here on the site, so I have resided in looking for a 2nd had ecu replacement, however, there are none to be found with the same serial numbers I got on mine (or does this matter??), so I'm in need of some help to locate any TD8 4.4's breaking that I can maybe contact to see if I can buy an ECU from them. I have already searched E Bay, Gum tree etc, but nothing there.
My ECU is 15K866-Bg SW5.4.4J CODE31.
Thanks for any replies on this.