Hi chaps
The soldier in the ww2 pic has what looks like a rolled anti-gas Cape on the top of his pack.
It kind of looks like the mini is carrying the same thing, though it's the first time I've seen one portrayed in such a way. Though it does appear to be attached to the two webbing suspender straps at mid chest, which perhaps makes it a possibility.
The BREN spare barrel bag is as shown in the parts photo above and the tool wallet was much, much smaller (being more of a wallet).

EDIT: fat finger typos!