I recently lost the top part of my drive mode selector **** and have been looking for replacements or another one for a while as it was scratched up anyway. Does anyone know where to find these? Just the cap would be great! That red arrow is where it would be

 

Looks like you can only buy the entire assembly from Lexus
https://www.ebay.com/itm/352667051437

3D print a replacement?

 

a junk yard. those caps just pop off, get a flat screwdriver and pry them up.
mine just popped off after the outside air temp hit -15F overnight.

figure out the orientation BEFORE you take off the old ones

 

It’s the same as RCF.. Gotta buy the entire control assembly.