Go into the link at the top of this page. I got ski cover only for £33.90 for 2 adults. It includes medical cover including mountain rescue etc of £5,000,000. We have an annual travel policy for ordinary cover so this met the case exactly.
click on box insurance, input your details, click skiing and search. Look through many policies, cover and conditions, maybe one that suits you and apply online.
I was impressed with the level of cover also. It even gives cover for piste closure and guess what Bansko is closed at the moment. Shan't panic yet though as I've still got 10 days to go.