Hi Odinn
Yes, your failure is just about in the same place as mine so it must simply be a design weakness. The plastic section as far as I can remember actuates the limit switch by following an inclined metal track. It has to be able to follow both sides of the track so that it can return to the original position. You still have a decent length of plastic to hold a spring in place so you should be able to fix that one.
I think that the rubber section that you found is probably just a cable retainer - see photo below
Regards
Geoff