Not sure if you're asking where you can buy another older Jazz or where you can get a value for your car.
If the former, have a look on Gumtree, Shpock, Autotrader, Motors, eBay, Piston Heads etc. But I would always recommend getting a vehicle inspection by an independent expert especially if it is a private sale.
Normally insurance companies will get a technician (internal or independent) to value the car and they would normally look at Parkers, Autotrader, Glasses and other used car websites. This is usually very slightly negotiable if you have good reason - so worth thinking about what makes your car more valuable that other examples. Options and modifications don't normally help.
In my experience if the other party was to blame, my insurance company will request the excess back from the other party automatically. But you may want to check with your insurance company.