Ok I have verified that this plug is a ECA Coin Connector.  http://www.planetarypinball.com/reference/gamemanuals/The_Addams_Family_Wms/index.html#/117/zoomed - I have confirmed it is coming off J4 from the Coin Door Interface Board. 

The thing is - which electronic coin mechs are able to be used with this connector? - if any

Thanks