Three:
A2-HA
A2-BK
A2-Purple
As a side note: There has been an A2 Porcupine but that was standard HA.
Please note that it is superfluous to write "HA-III" or "HA3" etc.
Type III anodised is Hard Anodised so you need only write "HA" or Type III
SureFire's standard HA finish is a "natural" finish rather an specifically colour dyed.
It varies from dark slate grey to deep green-brown. It is not "Olive Drab" coloured which I would take to mean colour-matched to a Mil. Spec. Olive Drab standard colour.
As for locating rare coloured SureFires: Dealers aren't the best places to search because the vast majority of rare SureFires are never handled by Dealers since they are usually custom-made by SureFire and currently in the hands of private owners.
CPF's buy/sell/trade is a good place to hunt out rare SureFires. I suggest you start there.
Al