OT: Trackball balls?

Looking for a source of -- I presume -- injection molded balls as used in trackballs. Any pointers appreciated.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.