First given name, two initials for second and third given names, date of death, estimated year of birth, Australian State of burial, from a photo of headstone in a Facebook Post by granddaughter Rhonda Boyland (nee Anlezark) on 10 October 2023:
Arthur S A Radnidge
Died 26th August 1968 Aged 66 years
Also
Ruby Myrtle Radnidge
Died 30th May 1990 Aged 82 years
Our dear Nan & Pop
In God's Garden

Second and third given names, full date of birth, year of marriage, place of burial at Cessnock Cemetery, name of parents, photo of headstone, from Find a Grave website found in November 2023:
https://www.findagrave.com/memorial/144853557/arthur-stuart_augustus-radnidge
Name: Arthur Stuart Augustus Radnidge
Birth Date: 23 Jul. 1902
Death Date: 26 Aug. 1968
Death Place: New South Wales, Australia
Cemetery: Cessnock Cemetery, New South Wales, Australia
Father: William Radnidge
Mother: Mary Ann Radnidge
Spouse: Ruby Myrtle Radnidge

Place of birth from the Australia Birth records, found in November 2023:
Name: Arthur S A Radnidge
Birth Date: 1902
Birth Place: New South Wales
Registration Year: 1902
Registration Place: Singleton, New South Wales, Australia
Father: William Radnidge
Mother: Mary A Radnidge

Place of marriage from the Australia Marriage records found in November 2023:
Groom: Arthur S A Radnidge
Bride: Ruby M Keasey
Marriage Year: 1925
Marriage Place: Cessnock, New South Wales
Registration Year: 1925
Registration Place: Cessnock, New South Wales, Australia