Just looked on Quckfit & they have Firestone SZ70's for £53.90 each. Had Firestones on the Insight for most of it's life & they were fine, lets face it, a 1.2 Fiat 500 doesn't need mega performance rubber.
After more investigation, the quickfit price is then subjest to an extra £11.50 for valves, balance & old tyre disposal.
Looks like the Toyo PX4 from Blackcircles then for £60 each all in.