if you prefer North Island consider spending some time in Coromandel, too.
maybe contact these guys here for bed, breakfast and stargazing.
http://www.newzealand.com/us/plan/bu...and-breakfast/
edit: no, this isn't the one I wanted to suggest..... there is another hostel/B&B with an obs much closer to the coast... but you wouldn't need that Obs, would you. So just have a look at Coromandel in general
