Well since no one else is answering, i might aswell just give my two cents.
There are really good possibilities for both surfing and skiing, but you would really need to choose which you want to do more. I would suggest looking for a job around Queenstown to ski snowpark, but since its in the midst of the south island, you would need a car to get around some waves. And actually the car would help you to get around some skiing too. Its a nice place tough, i really suggest you make a go on that opportunity