Where did you find a Nichia M10 for sale? A google search does not yield anyone offering it in the first few results.
I know this is an old post, but did you by chance measure the MCPCB? I really like the size of this light but would want to reflow an emitter and I have never done that before. I saw MTN carries a 10mm MCPCB that is 1.65mm thick and didnt know if that was the right size.
That seems thicker than stock, but it’s not a problem.
10mm is smaller than the stock one so it’ll definitely fit.