A couple years back somebody was asking about blurring a texture and I stumbled upon that closed thread yesterday. There I saw a few posts I hadn’t gotten a notice about and one was a reply from Thatims3r trying to duplicate a game effect of looking down a rifle scope and blurring out the background. It was really close to working so I pulled it down and finished it up yesterday.
It isn’t perfect as you will see the edges of the screen wrap around the UV coords of the texture. Feel free to do whatever with it.