You will struggle to find these parts new. The fork tubes and mudguard are specific to the 4 B models and are no longer listed. If you do manage to find them I would think they are very expensive.
The gear change lever is however used on over 30 different Kawasaki models so might still be available.
The handle bar grips were used on over 70 different Kawasaki models.
Try HERE to see what they have. Again I think they will be expensive.
If folk in the UK have the parts you need I feel they will need new chrome. That too can cost a lot of money.
There is also a guy in Sweden who has quite a lot of NOS parts. I will try and find his details for you but again it will be at a price.
I hope this helps and your foot recovers well.
By the way have I seen you on the German twin site? Filippo?