Tucker bag
The swag would generally be carried as a sausage-shaped roll slung over the shoulder, and the tucker bag in front.
Bullockies and drivers of horse-drawn vehicles were not so constrained by the need for portability, so a greater quantity of food could be carried in a tucker box, as exemplified by the story of the Dog on the Tuckerbox.
The contents would be similar, though: salt beef, tea, flour and sugar or golden syrup and perhaps tinned jam.
[1] Train crews' tucker boxes would contain more than food: a tin plate, pannikin (small pan or cup), eating utensils and toiletries.
[3] "Tucker box" was a model of domestic chest freezer built in Australia under the Whirlpool brand name.
"Sundowner" could be applied derogatively as meaning one who arrives at a station too late to do any useful work, but still expects a feed and top-up of the tuckerbag.