In the preceding array of Asiatic Fleet auxiliary vessels mounting 5-inch guns, I forgot to include submarine tender Otus
(AS 20), but at the time of the war in question, she too carried one 5-inch/51cal surface gun and a pair of 3-inch/50cal DP guns on her fantail (a late summer 1942 refit and rearming at Mare Island would garner another pair of 3-inch/50s foward and replace the old 5-inch surface gun aft with a 5-inch/38 DP). See
Back in the SWPA, Asiatic Fleet submarines, whether the older S-boats or the newer fleet boats, carried either a 3-inch/50 or a 4-inch/50 (the more powerful 5-inch/25 wet mounts on board U.S. submarines were many months in the future), thus no need for any of the submarine tenders in that fleet to carry 5-inch/25 fixed rounds. So, another door closed in the question of what source, other than Boise
(CL 47), replenished Houston
's 5-inch/25 ammunition.
As Elrond utters in The Lord of the Rings
, Part I, our choices become slim.