The members, two from Edinburgh and one from Fife, were caught after a six-month operation by the Scottish Crime and Drug Enforcement Agency (SCDEA).
Over a three-week period in April 2011, officers from Operation Lomida intercepted the Scottish arm of the cross-Border group and seized more than 16.5lb of heroin with an estimated street value of £637,000 during a series of connected raids.
Previous court cases resulted in jail terms being handed to four men from Glasgow, Manchester and Rochdale.
The agency said yesterday's court action takes the total sentence for the seven gang members to a combined 40 years.
Mohammed Younas, 41, from Edinburgh, was sentenced to 10 years' imprisonment when he appeared at the High Court in Glasgow.
David Clark, 45, also from Edinburgh, admitted possession of drugs and was jailed for four years and two months, while Lee Chalmers, 24, from Fife, pled guilty to the same charge and was ordered to spend three years and four-and-a-half months behind bars.
On April 11 last year, officers from the SCDEA witnessed Ajmal Mukhtar, 39, from Rochdale, meeting with Younas and Clark in the Edinburgh's Alexander Street.
Later that day Younas and Clark were seen entering Clark's house.
During this time, Mukhtar drove to Kelty in Fife where he met with Lee Chalmers
The 24-year-old was later detained at his home after being found with one kilogramme of heroin.
Clark was detained at his home after a subsequent search recovered another kilogramme of heroin.
Mukhtar was detained after £1500 was seized from his car after it was stopped on Edinburgh City Bypass.
Younas was also taken into custody by police.
A separate action on April 27 resulted in the arrests of Daryl Hampson, 28, from Glasgow, 41-year-old Tahir Rashid, from Rochdale, and David Livesay, 35, from Manchester.
Officers witnessed Rashid's Range Rover travel from England to Glasgow where they observed Hampson entering the vehicle on Hanson Street.
Hampson was in possession of a bag that officers believed contained drugs destined to be returned to Rashid and Livesay.
When he got out of the vehicle Hampson was arrested by police in Glasgow, where he was found to be in possession of 3.5kg of heroin.
Rashid and Livesay were later stopped in their car on the M74, near Abingdon, following a police pursuit. They were detained after police recovered a further two kilogrammes of heroin.
Detective Chief Superintendent Athol Aitken, head of investigations for the SCDEA, said: "Today's court result sends a further message to those involved in organised crime that law enforcement agencies in Scotland are determined to detect and dismantle their criminal enterprises and bring those involved to justice.
"The individuals who were jailed today were involved in supplying significant amounts of controlled drugs. Drugs to these people are simply a commodity to be traded for money and influence.
"In our communities, however, drugs bring fear, intimidation and violence associated with this illegal trade. By securing the convictions of so many members of the gang we have been able to ensure their criminal activities can no longer endanger the public."
Hampson was jailed for six years and three months at the High Court in Edinburgh on September 16, 2011. Rashid was sentenced to five years and seven months' imprisonment. He received a further 18 months' imprisonment after pleading guilty to dangerous driving.
Livesay was jailed for four years and Mukhtar was sentenced to four-and-a-half years in prison in December 2011.