What are the NPHC flag origins?

The design of the harbour flag would appear to be based on the logo used by the harbour on its headed paper - an early example of corporate identity from 1906. It would be good to know if any light can be thrown on who designed the original graphic. Bounded within the words and split into three distinct areas are: in the top section, what looks like a ling, below that, the Stone Quay and lighthouse to the left of which apear to be a square-rigged sailing ship and possibly a powered vessel in the gaps, below the harbour view is a lugger, obviously alluding to the main trade of the port and its raison d'etre.

Other examples of the design may exist?