I am not familiar with marines of other country. But, I think that marines are independent of the navy somewhat in any country. On the contrary, SNLF was utterly a part of the Navy. It was only one of Navy units and it was equal to fleet on commanding or organization. I think that it is different from marines.
Japanese marines existed between 1871 and 1976. In Japanese, marines is called Kaiheitai and NLF is called Rikusentai. They are distinguished in Japanese.