I have seen some sentras with the rear tails the same. The other day i seen a blue one with like grey rear tails. I liked the way the look. They appear stock but I want to know where i can get them or where i can get aftermarket tails.
That 'blue' sentra was most likely an SE-L with the factory greyish center piece. You can get a fresh one from your dealer or save 20% and get one from Tustin Nissan in CA. Expect to pay like $175 or so.