10 new old stock phenolic disc from Player Piano Company in Wichita, KS.  Original part number 1718 (black - these are also available in tan).  Punched from phenolic.  13/16" OD, 3/32" thick, no center hole.

Many more restoration parts are available in my eBay store.

I'm Howard Gustafson and I've been a player piano technician since 1985.  I'm glad to answer questions about this item (or any other item we sell or you think we should sell) before or after your purchase.  My contact information is included with each shipment and you can also reach me through eBay.  Your success with my products is very important to me, please don't hesitate to contact me with questions or suggestions.