ALL the courier companies I have spoken to surcharge for the Isle of Wight, just as they do for the Scottish Highlands etc.
Its difficult to find a company the will deliver 70kg AND deliver to the Isle of Wight. Most companies will do one or the other, but cant find one to do both for reasonable money.
I haven't been quoted £50, if I had, I would have done it. Best I have had so far is getting on for £100.

I would drive there myself for that.