UK Shipping - Exclusions or postage surcharge for Non UK mainland islands

I am having a problem with shipping costs for UK offshore islands and Scottish highlands.

My shipping method is by weight calculated by the actual costs to ship to UK mainland addresses however despite restricting my store to United Kingdom only, the islands are still able to purchase in my store.

I would obviously welcome the business but I am selling at a loss to these customers because the actual shipping cost to these locations far outweighs what is being charged in the store.

Is there a way around this either by excluding these locations from the United Kingdom country settings or by configuring a surcharge on the postage for specific postal areas etc?

I would be very interested to know what other here in the UK are doing to get around the problem?

I can't comment on  what others in the UK are doing to get around the problem, but Shipping Director can deal with this issue