The 50 hr IF requirement isn't set in stone. I was employed by Air Nelson without it, along with a couple of other guys. I think the use it as a way to weed people out. If you are keen and meet the requirements keep hounding them. You may need to come over to show that you are keen.
Mt Cook apparently use to like South Islanders, is this still the case? When I was applying from Aussie I didn't get any acknowledgement from them.