Hi Garry, and thanks for posting the pics.
From what I can see, the engine shaft sprocket (that's the small one at the top of the primary chain) has extremely pointy teeth and is now unserviceable.
The cutter and secondary drive sprocket is also at the end of its working life.
The drum clutch sprocket seems to be in reasonable condition.
When the sprockets are replaced, the chains also would need replacing.
Garry, I'll bet that these are the original sprockets and chains and have done a great job for 30+ years.
I suspected that this may be the case when you said in your original post that the "clutch assembly/shaft is making crunchy noises....fine when engaged" This can be a symptom of worn sprockets, with a SB 45.
