As you know plastic parts are getting hard to find.

I have gone two routes to solve my problems...

1. 3D Printer - I purchased a 3D Printer Kit to make the parts I need. And although I have not completed my printer yet, I expect when I am done it will make some decent parts. (The one the link is a complete product - not the kit I purchased.)
   UP! Mini 3D Printer.
2. Instamold - But for light weight fast part making, I have gone to Instamold.
   Instamold and Permastone - YouTube
   Today I needed an adapter plate to be able to install a standard rear view mirror onto my FD (which does not use the universal mount). So, I:
   1. Got out the instamold
   2. poured the amount I needed into a glass cooking bowl
   3. added water
   4. microwaved for two minutes
   5. kneaded the molding material into the shape I want
   6. pressed it into the part (sandwiched between two metal pieces)
   7. tightened the mating screw to bring the two pieces together as the molding plastic squeezed out
   8. cut it off where it squeezed out
   9. let it cool. Once cool it will be hard.
      Part Completed in about 5 minutes

There are a lot of imaginative and creative people here. I can imagine there can be many parts made for your Mazda.

 

I know it's not on topic, but you can skip the adapter plate.

To remove the stock rearview mirror button do the following:

Require parts.
pencil torch
razor blade
pliers
1. Heat the bracket, constantly moving around button and glass (make sure it is not a super cold day either).
2. Keep doing this for several minutes.
3. Have a pair of pliers ready to check if the adhesive gets soft.
4. Apply more heat if needed.
5. Once the adhesive gets soft, twist gently and remove.
6. Clean the adhesive off.

 

Thanks for the suggestion. But for my purposes, I do not want to remove the stock plate, as I may decide to put the OEM mirror back later.