32/9SS was a common Pacific sceam in late 44 and early 45 but 32/3SS was also common and easy to confuse with 32/9SS in B&W photos. I have a WW2 Sub Vet friend and he seems to remember most Late war Fremantle Based boats wearing the Measure 9 or even some in measure 10.. I think the Flasher was a Fremantle Boat. After the war the "Standard became Measure 9 ( Still is ). Yet while I was aboard the SSB(N) 601 on westpac we wore a two tone paint job similar to 32/9SS.
Your heart should be your master here. I just completed a 1/350 "S" Boat in mid war colors of Black/Dark Grey which was a squadron "Interpretation" of measure 10...