Death in 1970 in NSW can be found here:
https://familyhistory.bdm.nsw.gov.au/lifelink/familyhistory/search
The Sydney Morning Herald
Sydney, New South Wales, Australia
Tuesday, 6 October 1970
Page 27
SEIM---The Relatives, and Friends, of the late SYBIL SEIM. of Glendon Road, Double Bay, are invited to attend her Cremation service: to be held in the Chapel of the Northern Suburbs Crematorium.
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The Sydney Morning Herald
Sydney, New South Wales, Australia
Friday, 7 July 1971
Page 27
UNION FIDELITY TRUSTEE COMPANY OF AUSTRALIA LIMITED of 2 O'Connel Street. Sydney the Executor and Trustee of the Will of the said Sibyl Gordon Seim who died on the 2nd October, 1970 hereby gives notice that creditors and others having any claim against or to the Estate the said deceased are required to send particulars of their claims to the said Executor at the undermentioned address on or before the 10th September, 1972 at the expiration of which time the said Executor will distribute the assets of the said deceased to the persons entitled, having regard only to the claims of which It then has notice.
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The Sydney Morning Herald
Sydney, New South Wales, Australia
Thursday, 15 July 1971
Page 29
$158,122 ESTATEMiss Sybil Gordon Seim, of Double Bay, who died on October last, left $158,122 to her family and friends. Duty is estimated at $62,000
.