I am not sure what "3e" is but I have a 3rd three seat bench in the back of my VY Berlina Wagon. I am very happy with being able to put the kids in and take their friends with us when we go out, and still fit the groceries in behind the rear seat. It was put in by the previous owner and was made with leather matching the rest of the seats. It is forward facing, with entry via folding down the 2nd row seat backs. Because the 3rd row seat is only rated for children my car now has 5 x Category 1 and 3 x Category 2 seats. The rear of the seat folds forward then the complete bench folds forward again to allow almost complete use of the boot space. If it needs to be removed so larger items can be put in the back with the normal back seats folded down etc, it is held in by two bolts (one on each side). The two outside positions on the seat have over shoulder retractable seat belts, the centre one has only a lap seat belt.
It was supplied and installed (with Qld Compliance plate) by Streetwise at Eaglefarm in Brisbane. 07 3633 6150.