Thingiverse--really interesting MIATA stuff there
 

If you own or have access to a 3D printer, there are plenty of interesting parts available to be made on www.thingiverse.com. Typing "Miata" in the search bar brings up all sorts of trinkets, shown below. Head on over if you have some time to burn.

https://cimg0.ibsrv.net/gimg/www.mia...cc4596f745.jpg
cam seal installation tool
https://cimg1.ibsrv.net/gimg/www.mia...39cf9bbaae.jpg
door bushing
https://cimg4.ibsrv.net/gimg/www.mia...0e374f106e.png
NB window control relocation plate
https://cimg3.ibsrv.net/gimg/www.mia...8181b837fa.jpg
Tons of universal plugs and adapters (can be resized)
https://cimg7.ibsrv.net/gimg/www.mia...67d415763b.jpg
transmission cork
https://cimg0.ibsrv.net/gimg/www.mia...20c942b1cf.jpg
3D printed fender vent