Thanks for your replies chaps. Very helpful. We're still a little sketchy on the details so I'm not sure how big the fjord is either but so far it's looking like Stachler Video-80, Canon 40x (if we can eek out the budget...which considering the type of shot, I think it should be considered). And I like the sound of the old school 'sports finder'...could come in handy.
Thanks again,
Simon Douglas.