The information I've read about front strut braces and the MINI lead me to believe that a strut brace is more of a decorative thing than a performance enhancer due to the rigidity of the MINI front-end.
And I can't imagine why a 45-degree angle carbon-fiber weave would provide any strength at all.
So, in the spirit of helping my MINI pals, I've found this site that sells carbon-fiber peel-n-stick vinyl, and if you wrap it around the cardboard tube from some wrapping paper, you should be able to make a strut-brace that looks great, and probably has the same measurable performance as this one for about US$20
Carbon fiber-like vinyl 
There might actually be front strut braces that do something for the MINI, but I suspect this one isn't one of them. I also understand that on other types of cars that are much more flexible than the MINI, that a front strut brace can make a difference in certain situations.
For dress-up, this is much cheaper, and WAY more fun when people learn it's a cardboard tube!