PT&I is established by law to promote exports activity and investment in the Pacific region.
Between 2012 and early 2015, Hunia made false entries in the agency's accounting system.
According to court documents, by November 2013, Hunia racked up a $9846 bill on a fuel card and a year earlier caused a loss of more than $20,000 to PT&I.
Judge Field said the defendant also misused an Air New Zealand card over several months for non-work-related travel.
"The offending took place over some months and you had a position of trust in that you managed the accounts for the company," he said.
Another aggravating factor was Hunia's comments to probation in a pre-sentence interview.
They showed a "strong sense of entitlement", the judge said.
Hunia complained to the interviewer that there were other people with their hands in the till and they were not being prosecuted like she was.
But her lawyer, Luke Wilson, said she was "deeply remorseful" and determined to turn her life around.
"She has very supportive family and friends around her ... they don't condone what she's done," he said.
"She doesn't ever wish to take on employment position again which involves handling of money."
Mr Wilson said Hunia had recently got her forklift-driver's licence and was completing a warehousing course.
When the allegations came out, head of PT&I, Trade Commissioner Michael Greenslade, said it was "extremely frustrating and very disappointing this issue occurred under previous management".
Hunia will serve her home detention term at a friend's Manurewa address.
