Need help with 2 45ACP hdstmps

I can’t seem to narrow these 2 down.
The top one reads MG 43 ZI(may be reversed) .45. Is this French or Australian and what of the ZI?

The bottom one reads SF 57 I 1 and I assume it means Jan 1957 and either

The 1st one is Australian. MG = Small arms factory #2 - Footscray, IZ is Mark 1 and Z is Nitrocellulose powder. '43 = 1943 :D

The second one, I believe is French. Dated Jan 57, I= may be the ammunition factory Issy-Les Moulineaux outside Paris. (Someone pipe up if I am wrong.)

just my 2 cents…

SF = SFM (Soci