The bike in your photo is the Thruxton GT by Mecatwin, so I assume they sell the mirrors. If you look at the pics of their bikes in the link below, they showcase several of their bikes with those mirrors installed (including the Thruxton).
Mecatwin is a French company, and I comprehend absolutely no French. And unfortunately only a few of their web pages translate to English. I'm not sure if they even ship to the US, but you might try contacting them... good luck w/ that.
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