Can I do something with this? What to do.. what people think

Shaft as can see.. backing plate witch I thought is steel teeth well there is none and front pulley teeth gone too, iv got new parts but not sure on shaft as it hard to push plate on and there a bit of play, and can see in pics what state it in, yeah it will have a bit of movement back and forth as nothing pushing against it and tighten up but.. shaft??

 

What happend ?

 

Variator worn down and shaft not looking too good, don't know if I replace new parts they will just crumble teeth again.. the groves have got ally in them so would clean them out anyway before refitting new parts just don't know if shaft is worn as well, but backing plate off varitor is made from steel, witch making me thing it done so real damage to shaft, just looking for some real advice from some one who knows what they are looking at lol

 

If you can see in pictures, front groves are big channels and towards the back there really thin

 

Yea I can see exactly what's wrong I wondered why it's worn down! did the locking nut come loose

 

Yeah mate.. owner before didn't replace nut I think.. when you should every time..

 

Ive seen this countless times, should be fine, torque it up properly.

 

Iv replaced all worn parts and down up to the right torque as scuba said and so far it's alright been out on it for a while today and it holding up well let's just hope it last! At least for a while lol was close to selling it as spares and repairs.. so glad I didn't lol