My Considered Opinion on Date is 1940, World War II & Hence the Use of Aluminium Instead of Brass.
SAR SOUTH AUSTRALIAN RAILWAYS BRASS TAG MECH BRANCH No 1207 c1930s
1937 SAR SOUTH AUSTRALIAN RAILWAYS WEEKLY NOTICE #9
1937 SAR SOUTH AUSTRALIAN RAILWAYS WEEKLY NOTICE #15
1937 SAR SOUTH AUSTRALIAN RAILWAYS WEEKLY NOTICE #32
1937 SAR SOUTH AUSTRALIAN RAILWAYS WEEKLY NOTICE #7
c1910 membership fob SAR South Australian Rail & Tramways Association 1464
