Car insurance for UK to Iran trip [closed]

My husband and I are Australians who want to buy a car in the UK and drive it to Iran through Europe (incl. Eastern Europe), Turkey, Armenia, Azerbaijan etc. We want to leave ASAP once we have the practicalities sorted.

Our plan is to then drive back to the UK by Christmas and sell the car there (this way we don't have to pay for export etc).

It has been much more difficult than expected finding out about insurance for this, and I was hoping someone might be able to help us. Most importantly, we want to have third party liability insurance for the entire trip.

So, our questions are:

Has anyone else done this trip?

Did you buy international insurance? A few insurance companies (including Clements that I read about on a Horizons Unlimited thread) have said they will cover us for Europe and Turkey, but not Iran (or the 'Stans' area).

If you did manage to buy international insurance that covered Iran etc, who did you go through and how much did it cost (roughly)?

The other option we are considering is buying insurance for Europe and Turkey, then buying insurance at the border for these other countries (eg Iran). Does anyone know if this is possible, or have you done it? Is it easy enough to do?

Any other tips on sorting out the practicalities for such a trip, especially around insurance, would be very much appreciated.

P.S. We are buying the car in the UK instead of continental Europe because as Australians on a tourist visa we can't buy a car in Europe without residency. We know that they drive on the other side in the UK, so are looking for a left-hand vehicle there (and if that's not possible, we'll just have to cope!)