When it gets to a 10mm of difference, you may run into trouble. Sure you can bend them out but when you clip in, the brake arms will flair out the side and too much bending may cause the arms to catch on your other bindings or another object. I would avoid that option. Brakes usually run around $45 and you could get lucky with a local shop that deals with Look/Rossi bindings that may have a spare set laying around.
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