Only available from fuel injection shops . But there used to be a place in Melbourne called sun diesel , never used them so dont know quality  best regards  Les

Hi Mick 

I am not sure what you have in mind for your new nozzles, are you going to fit them yourself ? !

When I was working on diesels I took the injectors out, usually when other work was needed, and took them to a well recognised diesel shop for checking. They checked them, checked the cracking pressure and the spray pattern. If they  could be adjusted to get  up to spec they were, or if they needed some 'reconditioning' they got that and/or new needles and nozzles. But they were trusted to make the call and I refitted them. Never had cause to complain. Usually improved the starting, clean running and reduced fuel use. A win, win, win. Money well spent and not a lot usually.  

Recently I had some conversation with a person who had an old tractor that was needing work. So he put in new pistons and sleeves, bearings etc. Cheap on the net but still a heap of money. Did the head and valves etc. He asked me about the injectors and I told him to do the above. But he found a Utube video that showed how to recondition them yourself. So he did that and the tractor started OK and seemed to run OK. Lucky him I say but I think he wasted an opportunity to get the job right, but he only wants a slasher to keep the grass down, not drive around Australia for years.  

Jaahn