Try firebond on a classic limited mileage policy,NIG is the insurance company firebond is the broker

(most brokers have quoted NIG as the company used)

Quotes are on a 1990 import G_limited

,declared mods are exhaust

, alloys

,front spoiler,
I'm twice your ages though

6 points and no no claims as ive had classic policy's for 8 years

,two windscreen claims,

agreed value on your description with no photos or any evidence needed

Policy came in at

£186+£15 classic valuation charge+£20 brokers fee total

£221 with optional national breakdown recovery at

£76,

limited to 5000 miles parked off road

Tried SKY couldn't touch it and they have a minimum policy of

£250 before they start and are not currently doing agreed values
Tried Adrian flux couldn't touch it and didn't bother to quote
Tried Swinton

£636
Tried Academy came in at

£295 but not agreed value they don't do imports on classic policy's,but didn't mind the Mods or convictions
all the above were priced this morning

a company called life sure put me on to all these brokers plus a couple more courtsey of SKY after they couldn't match Firebond
if anyone needs their number i can post it

,should be worth a try