Anyway, the new PM of Australia was sworn-in without much fuss by
their Governor-General providing the sumpah service for the
nation at a much cheaper rate.

Australia Governor-General
wiki --
Their Constitution does not set a term of office, so a
Governor-General may continue to hold office for any agreed length
of time, however a typical term of office is five years. At the end
of this period, a commission is occasionally extended by a short
period.
The salary of the Governor-General is regulated by the
Constitution, which fixed an annual amount of 10,000 pounds, unless
the parliament decides otherwise. The Constitution states that the
salary of the Governor-General may not be increased during his or
her term of office. Under the Governor-General Act of 1974 each new
commission has resulted in a pay increase. Today, the law ensures
the salary is higher than that for the Chief Justice of the High Court, over
a five year period. The annual salary during Michael
Jeffery's term was $365,000. Quentin Bryce's
salary is $394,000.[4]
Until 2001, Governors-General did not pay income tax on their
salary; this was changed after the Queen agreed to pay
tax.[4]
i searched wiki, but never get to understand the word "sumpah"
instead they show me sampan. Are you looking at the right wiki?