It is definitely pieced and not a panel, you can see the piecing seams in the eagle. It is entirely possible it is an original design or something someone came up with on EQ. When perusing Maniac's link I found one that looked a lot like this but lead to a dead end. I did find one that lead to a link for a pattern but the eagle's position was slightly different. Just as striking but it would take some work to change the star to be like the picture you posted. Both are a very clever manipulation of the diamonds in the lone star. Here is a link to the layout of the diamond units I found (takes a while to load)
http://orig02.deviantart.net/614e/f/...ts-d30jyig.pdf
Would still take some figuring out to strip piece.
And here is a link to the picture of it I found on Pinterest
https://www.pinterest.com/pin/313915036496481519/.