England take on Italy next weekend and Mallinder feels Hartley and Lawes' performances in the 40-14 win could have forced Lancaster to think again after he released the pair for the clash against the Exiles.
Opposite number and former England attack coach Brian Smith described Hartley as a "talisman" for the Saints pack, and Mallinder added: "I thought our two returning England lads were particularly impressive. Hartley and Lawes put their bodies on the line and were very, very good."
He added: "Courtney has come back with a real determined attitude. He was frustrated from his performance for England against France, he is an honest guy, he doesn't hide away. But his work rate and physicality was immense today.
"I hope Stuart watches the game because then it will give him a few more selection headaches.
"I am only guessing, but probably in the back of his mind those two would be on the bench for the Italy game. But with their performance today the pair of them really put their hands up for selection."
Jamie Elliott scored a hat-trick of tries with Soane Tonga'uiha, Samu Manoa and GJ Van Velze also dotting down for Northampton, as they moved up to fourth with five games to go and without the distraction of Europe or the LV= Cup.
"It was an essential win to get us back into the top four," said Mallinder. "We have had a few ups and downs, but we will get all the England lads back for the next game and we are in a decent position."
London Irish director of rugby Smith admitted his side were blown away in the second half after coming in at half-time unlucky to be 14-9 down.
"They ran riot in the second half," said Smith. "We had a couple of scoring chances in the first half and we really needed to take them, we had to score at least twice from our trips to their 22 in the first half and we didn't do that. The second half is one we would rather forget."