Despite the cash offer, and a major police investigation spanning more than 26 years - dubbed Operation Darlia - an arrest is yet to be made.
Furlong's was the first unsolved murder to feature on the new series of TVNZ's Cold Case, which aired earlier this month.
On the episode police revealed that they had identified a person of interest.
While they did not name the person, police said he was an "associate" of Furlong and Norsworthy who had strong connections to the Port Waikato area.
Detective Inspector Paul Newman said this week that a small team was currently working on Operation Darlia and since the show aired information had been coming through.
While it had slowed down now, officers were working through tips to see if they led to any answers.
"We have some leads which we are following up, said Newman.
"Fingers crossed."