just contacted them, the rates (in case people are interested) are
Jap Fest if you are doing either 1 or 2 x 15 min sessions
Option 1 Option 2 Option3 Option 4
Sum Assured 5,000 8,000 11,000 14,000
Excess 750 1,000 1,250 1,500
Cover 4,250 7,000 9,750 12,500
Premium per Track Day £60 £80 £100 £125
Option 5 Option 6 Option 7 Option 8
Sum Assured 17,000 22,000 27,000 32,000
Excess 2,000 2,000 2,000 2,000
Cover 15,000 20,000 25,000 30,000
£140 £160 £200 £225
All cars MUST be insured for around 50% of the total value
sorry if it doesn't line up right, but you should be able to work it out..
seems pretty pricey, but would definitely give some peace of mind...