I was swapping out LEDs in our '16ES.
I got to the driver's vanity light and discovered it was not turning on when the mirror door was opened.(the standard bulb not the LED). if I had half a brain I would have taken it in under warranty for repair, but Nooooooo, couldn't do that had to check it out myself. Actually I thought I might have screwed something up when I wired in the Radar Detector,
So I pop the mirror housing to see if I can check the switch. Unfortunately, I cracked the mirror in the process. On the positive side, after playing with the switch and putting the housing back the light started working.

What follows is the reason I'm posting - the solution
I called Lexus and they do not sell replacement mirrors, you have to buy the whole visor - $140 + labor.
I went to a local glass place and they cut me a new mirror $4.50. It was a bit thicker than the original but fit. For some extra security, I used some duct tape to secure it the housing. The unit went in, the light works, all is good.
I also tried looking on E-Bay for used ones. I could only find '09s.$18-$20. I'm not 100% certain but it looks like the housing is the same size for the 2 cars. The housing in my '16ES measures the same as the one in my '10 IS-F.
If my fix doesn't hold up I'll probably try one of these.

Finally, Lexus has tape on the back of the OEM mirror. It is what kept glass shards from falling on me and allowed me to take the mirror into the Glass place to cut the new one.

 

If you end up having to buy a new one, at a discounted price.

https://www.lexuspartsnow.com/parts-...html?PNC=74320

 

Thanks looks like a good site to bookmark.