How do you dissemble a Comet CAT 99 driven pulley?

[Rapidrob]

I have what I think is a comet CAT 99 driven pulley that is asymmetrical but does not have the Snap Ring to gain access to the inner components. The plastic Buttons are badly wore and need to be replaced.
The only ID on the pulley is Comets address, Richmond Indiana and a large letter "A". it is a 6" pulley.

 

[Rapidrob]

Playing around I found the spring "spider" is screwed onto the bearing shaft with Left Hand threads. Easy Peasy.
Now if I con only find the plastic buttons for this driven pulley.