He said he was also concerned about out-of-context publicity in the wake of alleged threats to poison baby milk powder.
However, Judge Mark Callaghan declined the application. Veint was convicted and fined $500.
Prosecuting Sergeant Ian Collin said the firearms were found unsecured around the property.
A Benelli shotgun and ammunition were found under the couch in the lounge, Sgt Collin said, while a .22-calibre rifle was leaning up against a bedroom wall with ammunition close by.
The .308-calibre Tikka hunting rifle was found on the garage floor underneath a blanket with a magazine containing three rounds attached.
Mr Mooney said a conviction could affect his client's ability to work as a hunting guide and travel to the United States and Canada.
But Judge Callaghan declined the application, saying: "The fact you may be discredited as a potential Member of Parliament is something the public should know -- that there are circumstances in your past that might affect your credibility."
The judge said Veint's failure to renew his licence for 18 months was "a concern to the court", and categorised the offending as low to moderate.
"While there is no suggestion of misuse, the method by which they were left randomly about the house is a concern not just for you but for others who might have come into the house."
The judge said he assumed Veint had been using the firearms regularly as a hunting guide, but Veint told police he had not renewed the licence because of the expense.
Judge Callaghan said: "I cannot see, when I weigh it, how the consequences of a conviction would be out of all proportion to the gravity of the offending in this case."
Veint, who had a licence for more than 20 years before his failure to renew it, had completed 33 voluntary hours of unpaid community work and the Mountain Safety Council's firearms course between his arrest and sentence.
He was also ordered to pay $130 costs. The case was stood down until this afternoon while inquiries would made about a possible destruction order for the firearms.