Kona kai still exists, its now a Polynesian restaurant in Athens at Marriot Hotel's basement. It opens 7:30 evening. It is a fair Tiki bar with a touch of European Classics. As a part of a five star hotel, it offers very tasteful and sparingly decked out, but overall, impressive. Their bar area offers a decent selection of Tiki mugs but still could match the original Kona Kai mugs which is now long gone.
More Details on the link below.
Link: Kona Kai – Athens Marriott Hotel