I am not sure if the kicker uses the same plunger as the flipper which you reference, but typically I think they are different. Unfortunately, I can't get to my machine to confirm, but I think you need an assembly such as this...

https://www.marcospecialties.com/pinball-parts/A-16700-GTB

You could always try just a plunger such as...while reusing your kicker arm.

https://www.marcospecialties.com/pinball-parts/22425

Also, I would highly recommend confirming the part numbers via the manual if possible. The parts I linked were based on the "look" of your image.