Part number, part drawing, and plan for attaching

[Sebastian-Thompson]

What is the part number for flex coupling in the first image? Does the black know need a hole drilled and tapped for a set screw or was there a different plan to attach the knob to the motor? (see second picture)

[ksunden]

https://www.amazon.com/dp/B07TXG1YNK

This is the coupler I bought, but they are honestly a dime a dozen, there are many compatible parts (very common for 3d printers, standard size of 5 mm on one side, 8 mm on the other

The other side can be epoxied in place. Originally I was going to cut a hex head in to interface with the knob, but after talking with Steve decided that epoxy would do for the loads expected here.