These buttons tend to get sticky and gross as their silicone coating degrades, and I wasn't able to find the models for free anywhere so I modeled them myself.
Print in the orientation shown in the slicer screenshot with support enabled. Lower layer heights will look and feel nicer as these parts are fairly curved (I normally do 0.08), but the ones pictured were printed at .16mm and turned out fine.
Do not install the springs on the star power button during reassembly. You may need to lightly sand the “legs” and the little notches to allow it to slide freely. I like to apply a bit of lubricant with a qtip but that is likely overkill and uneccesary.
Make sure to transfer the little silicone guys on the start buttons.
The start buttons are slightly taller than the originals because I did not like that they were recessed.
Both parts are in the f3d file I have attached, so feel free to tweak/remix them as you like.
The author marked this model as their own original creation.