How to save a cover rubber of gearbox shift ???

[T_AE86]

Hi, i searched in the forum but i didn't find it.

I put on a T3 quick shift, and all was Ok, but the problem is that Toyota hasn't for sale the cover rubber of gearbox shift (not the boot), And i can't find a way to remove the rubber of the original shift, because below has the "rolling ball" with biggest lever balls and above a thick tube

Anyone know how to extract it?

This is the rubber:


Rolling ball below:


Thick tube above:


Thanks. Regards