New old stock Rockwell Delta Overarm Router / Shaper Spindle Assembly Collet part number 432-04-385-0002.  Includes Coupling part number 432-04-028-0001.  Spindle assembly has a list price of $297.11, and Coupling is $137.63.  This is for the upper motor/spindle of the machine, and is the newer style, the bearings are slightly smaller then what the older style used.  Confirm with your parts list to make sure the part will work for your machine.