One of the caps for my MJX HyperGo 16208 is damaged and wont stay on the cap, so i redesigned it, ofcourse, without the cup, just as a seal. it can also increase the shock absorber few mm, depending how thing you want to make it.

There is absolutely no difference between the stock cap and the seal, most of the shock absorbers dont have that cup, just a seal.

Print it in TPU, high temperature, low speed,

You can increase the width in the slicer. its just a round cap.

Print suggestion: instead of 100% infill, just increase the number of parameters, it will make it stronger and with better layer adhesion.