Reference a different culture model for ports

[Epistolary Richard]

Are the port models on the strategic map connected to the current occupier, the faction_creator of the city or the constructor of the current government building?

I want the port of Rhodes to reference the barbarian port model entry on the strategic map at the start of the game - is there any way that this can be done but have Rhodes itself still appear as a Greek settlement? Note that I want it to reference the entry not the model itself so I can't just swap the models around. I then want to change the model so that the port of Rhodes looks different to every other port on the map.

[Dol Guldur]

Can you not just block the building of a level of ports from the rest of your regions by use of a hidden resource and then make whatever model you want for Rhodes by using that reserved level?