The 26-year-old left the Gills for the Cobblers in the summer of 2007, and has played in midfield for much of his career with them, having been primarily a left-back in his spell at Priestfield under Ronnie Jepson.
And Stimson said: "When I first saw Danny play against us he was the best player on the pitch. I'm surprised he was let go.
"He's a player I've admired for a while and I'd love him to come back.
"He would be a great addition to my team because he's got what I love in a player and that's enthusiasm as well as that other ingredient you need - a bit of quality."