There is a vacancy at Ibrox after Durrant and Rangers parted company on Thursday.
McCoist has been out of football since quitting as Rangers manager in 2014, having won two promotions with the Gers following their financial meltdown in 2012.
He also enjoyed a hugely successful playing career with Rangers, netting 251 times in 418 appearances in a goal-laden 15-year spell which yielded 19 major domestic honours.
Kenny McDowall is also free at the moment, having been McCoist's number two in the dugout and later Rangers boss in a caretaker capacity following the 53-year-old's exit.
And Johnstone has suggested that the duo could get back together to replace Durrant at Ibrox.
"It won’t be the end of the road for wee Duranty. Ally McCoist has said he wants another job so who knows," he told The Glasgow Evening Times.
“Maybe that’s the way it goes. Kenny McDowall is still out there, too. Ally is desperate to get back into football. Maybe the three will get back to together.”
McCoist remains revered on the blue half of Glasgow and surely supporters would love to see him return, despite the low-profile capacity, but it remains to be seen if he would accept the role, having sat in the big seat for three years.
But times are better now and Rangers are preparing for their big return to the Scottish Premiership, with Mark Warburton finishing the job McCoist and his colleagues started what seems a lot longer than four years ago.