What size boat? your going to need a BIG boat possibly a Professional Cray / fishing boat of at least 50+ ft.
Have a read of a recent thread about sailing to King Island.
www.seabreeze.com.au/forums/Sailing/General/Anyone-sailing-to-King-Island/PS; take plenty of seasickness pills with you, looking through a camera view finder on a rocking boat is one of the most rapid ways to get crook

and stabilised lenses are even worse.