Gary,
weelcome to the NMB forum!
There is not much you could do yourself to improve the condition of these swords except giving them a thin layer of low viscosity mineral oil AND wiping it mostly off so no oil gets into the SAYA (= scabbard).
But luckily you have a real expert in Australia who you could ask for help:
Andrew Ickeringill https://touken-togishi.com/
He will probably not work on these machine-made military blades but he could advise you what to do.
In the meantime you could clean the red rust off the NAKAGO (= tang) just with a cotton rag, a soft brush, and A LITTLE oil. Nothing abrasive, so the patina is not damaged! This is normally not done on traditionally made Japanese sword blades, but in your case, it is all about preserving a piece of recent military history.
Be patient as you clean, as damaging is easy!
The MEI (= signatures) are nicely readable on two swords; they were probably made industrially in MINO province in the war.