Giorgos Chatzifotiadis, 77, broke down in Greece's second city of Thessaloniki last week and cried in despair after he failed at four different financial institutions to withdraw a pension of 120 euros (US$132) on behalf of his wife.
The picture of him sitting on the ground was captured by an AFP photographer and went around the world, starkly illustrating how ordinary Greeks are suffering during the country's debt crisis.
James Koufos, an Australian-born chief executive of a finance firm, saw the photo published in Sydney and thought the retiree looked "so much like a friend of my dad's".
The 41-year-old said he was talking to his mother, who lives in Greece, on Facebook and she confirmed Chatzifotiadis was an old friend of his late father, who died 18 months ago.
"When I saw this, I said to mum, 'What can we do?'," Koufos told AFP.
"I got my mother to take out some cash, to find the man and give him some immediate support."
Koufos also put out an emotional appeal on Facebook to locate Chatzifotiadis, and has since set up a trust fund welcoming further contributions. He is set to depart Sydney on Saturday for Athens, before heading to Thessaloniki to meet the pensioner.
"We're going over there to surprise him and just give him quite a substantial amount of money, plus we're also raising some money now from corporations... who want to donate," said the businessman.
They aim to offer help to others besides Chatzifotiadis wherever they can, he said.
"We're dealing with a few places that deal with shelters in Athens and Thessaloniki to offer immediate support where we can with shelter and food."
Koufos' family is also from Thessaloniki, and Chatzifotiadis even attended his sister's wedding.
Australia is home to a large number of Greek migrants, with the city of Melbourne having the third-largest Greek-speaking population of any city in the world outside Athens and Thessaloniki, according to Australian government statistics.
Koufos, whose parents hail from Greece, said he became emotional after viewing the photographs as they "told a thousand stories".
"Those photos had such an impact, not just on me, but a lot of people I know," he said.
"I've had grown men that I know in front of me and over the phone bawling their eyes out on just how much it hit them."
European leaders have given Athens a final deadline of Sunday to reach a new bailout deal and avoid crashing out of the euro.
Greek voters rejected international creditors' plans in a referendum over the weekend.