Option 2: Establish SMBE national executive

An SMBE national executive could comprise the President of each existing state society from amongst whom a chairperson could be nominated.
It should not be necessary to have other appointed officers at this level: the secretariat/treasury function could be rotated between states.
Discussions and affairs could largely be conducted by teleconference, with consideration perhaps being given to one face to face meeting each year at the national conference or other event.
These communications channels would need to be funded, this could be with a per capita contribution by each state to a national executive fund. Assuming teleconferences would be the initial means of communication something of the order of $1 per member per annum should adequately fund this activity.
Difficulties occur in there being continual rotation amongst members, also where States have no SMBE or an inactive SMBE: e.g. QLD, NT, WA. The State Exec will tend to oscillate between having the same membership each year (as the SMBEs do), and having complete new membership with no memory of goals and actions.