cost of run flat tires installed

Run flat tires are not readily available. I have found Michelin Pax only at Honda dealers.

You are right about how hard to find run flats. Most tire shop won't sell them. I think one of the biggest reason for this is because most of them gets really noisy within the warranty period. I have seen many vehicle owner who just replace them with good quality tires and either keep a donut spare tire in the trunk or few cans of "Fix a Flat". Zee