The photo was supplied to www.moke.com.au by Chris Tyler who has the original photo that was given to him by a fellow he used to work with that was in the Army so no information is available about the source or location yet. All other comments are based on looking closely at the original photo.
The first thing I noticed about the Mokes pictured is there lack of the perspex sidescreen and blank panel of the canopy that was a feature of the earlier Mokes. This along with the combined indicator and parking light and flat bonnet suggest these Mokes are very early 13" wheeled Mokes from around 1968 or 1969.
However according to the List of Australian Military Mokes only two Mokes were purchased for evaluation in 1969 and no further orders were placed until 1973. So if the assumption is they are for the Australian Military then either the list is wrong or not complete.
The obvious military extra on here is the snorkel with pre-cleaner on the left side and the military plate holders on the front bumper. What is missing though is wiper arms. You can also see on the badge on the front panel the use of two words so it is likely to be 'BMC Moke' which again gives the vintage of these Mokes as '68 or '69.
You can just see the front of another Moke on the left edge of the photo that has no canopy and what looks like the windscreen folded down on the bonnet. This means at least 10 Mokes were delivered at the time of this photograph. A little more obvious in this close up is the non standard sump guard on these Mokes.
These are a couple of other crops from the image that might help identify the location.