It was Scott Dean Crowther's job to collect money owed to the syndicate when called on by its principals, Coniston twin brothers Joel and Flinn Westman. He was a user of a drugs the syndicate traded in - MDMA and cocaine.

Investigators were listening in on July 14 when Crowther, in Queensland, spoke to the twins about a customer with a $18,000 debt. The twins paid the man a visit and called Crowther a short time later, so he could help them extract the debt, over loud speaker.

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"You owed 11 then you got an occa so that's another seven and a half, you took the product, you pay for it," Crowther was heard saying.

Flinn Westman allegedly then threatened to "slice" the man if he didn't give the twins his car as payment. Crowther directed Flinn to punch the man.

Police allege the syndicate went on to use the man's BMW to run their day-to-day business.

Police recovered an air pistol, expandable baton and knuckle dusters after swooping on Crowther's family home the following month. They also found a police patch and the name badge/plate of a serving NSW Police officer.

The 35-year-old was arrested on October 11 and admitted to having bought the weapons off the website Wish.

In Wollongong Local Court on Tuesday morning he was sentenced to a term of imprisonment of 16 months, with a non-parole period of nine months. With the sentence backdated to March 27, he will become eligible for parole on December 26.

Crowther has since lodged a severity appeal.