Well back then a person who was born in Australia was also automatically a British national, and there is only one death registration for a British national called Beldon who died overseas, and the name, the age, and the place, match Florence.
You can get a copy of the death certificate for about £10 from the U.K. General Register Office
( GRO )
http://www.gro.gov.uk/gro/content/Death registration...
GRO index to Consular deaths 1931-1935...Beldon, Florence Elizabeth...age 48...
Consulate Shanghai...Volume 28...Page 52