The knife that was recovered after the burglary - it is identical to the missing one, apart from a bullet mark.
A Whangārei father and son are searching for an irreplaceable heirloom stolen in a burglary in May.
A Gurkha knife Albert Griffiths carried in World War II, which saved his life by stopping a bullet from a Japanese sniper, was stolen from his grandson's Kamo home in May.
Albert, who has since died, served in the SAS during the war, where he fought alongside Gurkhas - Nepalese soldiers recruited by the British Army - and carried two of their traditional kukri knives.
The weapons are carried in pairs, but just one of Albert's had a mark on it where it was hit by a bullet.
"My father was behind enemy lines and he got shot by a Japanese sniper and the bullet hit the steel of the blade," Albert's son Trevor Griffiths said.
Both kukris were stolen - along with many other items including a motorcycle - but one kukri, along with some other items, was returned by police. The one that saved Albert's life remained missing.
Trevor and Dominic decided to put the word out on social media over the weekend in an effort to get the knife back, after hearing about a person who found a dog missing for three months through social media posts.
"We were having lunch together on Sunday and we were both getting a bit emotional about the fact that we'll never see it again," Trevor said.
Albert would have marked his 100th birthday in August 2021, but passed away at the age of 97 and three-quarters.
"I said I'll pay a reward but I didn't put a figure on it - to me it's irreplaceable. If it's $500 or $1000 I don't care, we just want to get it back.
"It's just a token gesture if someone's got to go out of their way to help find it."
The posts have been shared on numerous social media pages in just a few days, even by a man who runs a memorabilia website in the UK.
"I didn't think there would be any chance we would get anything back, but my son said, 'hey Dad, let's put it on Facebook' and bugger me, it's gone around the world."
Trevor said he was sure he would know the distinctive weapon if he saw it again.
"I'd recognise it in a heartbeat with the bullet hole in it. As a kid, I used to play with that knife - safely obviously."
Around 250,000 Gurkhas from Nepal and some parts of northeast India fought in the British Army during World War II.
Their weapon of choice was the 46cm long curved kukri.
Gurkhas also fought for the British in World War I and a number of earlier wars.
A small number of Gurkhas recruited from Nepal still serve in the British Army. In 2009, they were given the automatic right to settle in the United Kingdom after retirement after a long legal battle.