Since we are talking patches can someone enlighten me about these? Belonged to my uncle who was a Navy radioman C3 in WWII. Thanks.
I think you will find this article from the Naval History and Heritage Command of interest to you;
Naval Amphibious Forces Shoulder Insignia
I was an amphib sailor (Gatory Navy) in Desert Shield / Storm - deployed with ARG Alpha
as for the two chevrons, those are 1 (first class) and 2 (second class) that are cut off for a 3 (third class) rating badge.
all blues and whites rating badges are made as first class with three chevrons, the sailor (or their uniform tailor) cuts off the unused chevrons depending on their rank.
3c is an old method of reference to a third class (E4) that would wear one chevron on his rating badge, hence the remaining two cut off that you have.
Radioman is no longer an active Navy rating of it's own, however the rating badge looks like this;
Radioman (RM) Navy Rate Patch 1st-3rd Class