Replace xg1p with xg1v4 cable box

Hi, I am trying to replace my xg1p with an xg1v4 cable box. I have visited my local xfinity store and they do not have stock. They placed an order for me and sent me a wifi box that didn't work with my TV. I'm hoping this forum can help me replace my old xg1p box with an xg1v4 cable box. Thank You.