I think you may have moulded on to the shaft one's if so. This type can not be removed like the screw on one's and will need to be replaced as a whole ie Bat and Shaft complete. you can buy these from PBR or Pinball life may have them
hope you're wrong as I have the replacement plastic bats, but thank you for the tip if needed
You can use the molded ones but you have to grind the groove in the shaft to allow for the grub screws.
