Sphere
sketchfab
Let me try that again. It's super frustrating trying to locate a straightforward sphere to download from this site, so I went ahead and created one for you.
Download Model from sketchfab
With this file you will be able to print Sphere with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Sphere.