Disco 1 Insurance for 3rd Party sat in a field!

I am insured with Adrian Flux for all of my policies - 4 in total.

We have a Disco 1 (1995 300 tdi) that is sat in a field that my sons drives around, never goes out on the road and we insure this 3rd party fire and theft (just to be on the safe side).

We only got this last year, and insurance with Adrian Flux was £80.00 for the year. This year it has increased to just under £120.00 which seems steep for this kind of policy, and they will not budge on the premium too.

Does anyone else have this sort of policy and if so, is this premium reasonable, or should I be looking elsewhere, and where should I look for this type of policy?

Thanks guys

Remember that insurance tax went up today. http://www.bbc.co.uk/news/business-40107955

I appreciate that, but got my quote a good few weeks ago, and also never expected a 50% increase - a little steep to me.....

Last year my 3rd party cover on my 300TDi with Flux was £221. This year they wanted £520 for the same cover, same risks, no claims or accidents, no convictions, no losses.
I went elsewhere via the 'Meerkats' and paid just under £300 for 3rd party. Because it is a second car I only have 1 year's NCD.
Shop around is the order of the day with insurance.

Adrian flux are doing a laid up policy now for £38 which is fire and theft only, so that's what I will be doing this time.

Flux,
Good first year price then it's a big hike for second year.