What Can I Do? Insurance Renewal Too Expensive

Recently became unemployed.

In my 30's, 8 years protected NCB, 3 points for speeding.
1 accident my fault 4 and a half years go
another accident not my fault 4 years ago.

I used to use my car through a specialist modified car insurance broker.
12k miles a year
Social and commuting
Parked in an open public car park during the day (when i was working)
Approx £400 a year
Working in IT

I updated my details to reflect i'm not working as my renewal came through at 400 again but it would be with me employed and stuff.

I change it to
6k miles a year
Social only
Unemployed
Parked in street during the day

Sadly now my old broker won't quote me unless i'm working and the cheapest i can obtain insurance is £900.
I can't afford it.
It seems although i'll be using the car much less than i used to, the risk is much greater "statistically" as i imagine unemployed people are at higher risk from more claims or something.

The next problem i have however is my insurance is due in approx 1 week.
With no insurance i need to declare the car SORN
But i don't have use of a driveway to put the car.

So looks like i have approx 1 week to sell my car.
It never rains but it pours....