SA Medics Badge

[Alex Rice]

Hi All
I have recently acquired this badge, which is obviously South African and with a medical symbol, but I have never seen anything like it before. It looks like a cap badge, so maybe a prototype?
It has the Lion of Nassau which is usually associated with SA Navy badges, so maybe to do with the Naval Medical dept from before them being joined with SAMS?
Any advice/opinions welcomed. Thanks in advance.
Cheers,
Alex