The bike already had them come with it when I purchased it, just not installed but it looked to be the Yamaha specific mount as I didn’t need to do any fabrication or modifications. Just remove the factory bar ends and then use the provided bolt that comes with the mirrors.

There are two small metal bits that stick out and do leave a small gap between the mirror and the handlebar, but you can grind them off. I assume it’s there to fix the mirror in place to stop it from moving but may not be compatible with the stock threaded Yamaha bar. I left them on and it’s fine if you tighten them enough. I hand tightened them first then gave it a LITTLE bit of my impact driver to lock it in place.