Doesn't vx-3 have a gold ring on the objective and the mark 4 had black?
Unless leupold changed some things since my old vx-3 something looks off. I could be wrong i havnt baught a vx-3 in well over a decade. I would call leupold.
It looks real to me, however a quick call to Leupold will let you know for sure. I have called them several times asking if scopes were legit, it's fast and easy.
DW