All good now. Flashers working properly and the car now registered and back on the road.

I followed good advice and replaced all bulbs and then I found that the problem was, as suggested,
bad contacts in the bulb holders within the headlights.

Looked like this problem happened before as there was an attempt to fix up the contacts in the bulb holders by adding
solder - I cleaned it all up, carefully added solder and problem gone.

Tomorrow the car is going in for body repairs after negotiating with the insurers (since the February 2024 accident) of the party
at fault. It is going to cost them quite a bit owing to parts scarcity, cost of skilled labour, cost of replacement car for the duration, etc.

Anyway, thanks everyone for the good advice and I hope to have a properly presented car back on the road soon.

BTW the CCs are becoming very rare in Sydney.

Ron