The pact saw 21-year-old left-back Paul Dummett arrive in Paisley on loan last August before midfielder Connor Newton, also 21, followed on another temporary switch in January.
Both players were involved in the club's 3-2 win over Hearts in the Scottish Communities League Cup final on Sunday as they ended a 26-year wait for silverware with their Hampden success.
Now Spencer Downey - who works closely with Newcastle - claims the Premier League giants will send more of their talented reserves to Scotland to speed up their development.
He said: "We're already looking at the next batch to send north.
"It will be hard to manage the expectations as Paul and Conor have done so well that people will think everyone we send up will be just as good but we are working on picking out the best young players for St Mirren to look at.
"What St Mirren have achieved this week has been unbelievable and it's made the people at Newcastle sit up and take notice."
Both players played key roles in Saints' League Cup victory.
Dummett set up Steven Thompson for the team's second goal, while Newton scored the crucial third to hand Danny Lennon his first trophy as St Mirren boss.
But the duo are out of contract with Newcastle at the end of the season and Downey believes they would have no problem signing on with the SPL outfit permanently.
"Conor has really taken the club to his heart and Paul is the same," he said. "In fact, Dummy told me the other day his dad is even talking about getting a St Mirren tattoo.
"The way the club have treated the two lads has been unbelievable. From the chairman Stewart Gilmour, to the chief executive Brian Caldwell and then both Danny Lennon and (first-team coach) Tommy Craig on the football side, they have all been great.
"If prizes were given out for being nice in football, St Mirren would be in the Champions League.
"Dummy has come on leaps and bounds while Conor has stepped up too. I think people forget that the semi-final against Celtic was one of his first games ever at first-team level.
"But he looked like a seasoned pro that day, even though he was up against star players like Victor Wanyama and Joe Ledley.
"He set up the first goal in that game and now he's scored the winner in a cup final. It's Roy of the Rovers stuff.
"So Newcastle can see the value in sending their lads north. And it can work both ways. Saints have young guys like Thomas Reilly and John McGinn who, if they continue to develop, could benefit from the partnership."
But Saints have been warned that Dummett and Newton's Hampden heroics have alerted clubs down south to their talents.
He said: "St Mirren are very keen to keep them around but we have had enquiries from clubs down south. There's one club chasing promotion from the Championship and another at the bottom end of the Premier League.
"They have been impressed by what the lads have been doing and where they have been doing it."