Tartan,
I have a boxed set of Grist attachments for a shuttle machine that came with two front slide plates. One has an underbraider attachment and one is an edge stitcher.
The problem is I have no idea what they fit.
I've also got a box of goodies that have an underbraider and a edge stitcher that clip to the front slide plate, but they don't fit anything I have checked. They might fit my Franklin as that is supposed to be a copy of the Singe 27. I'm gonna have to dig it out and see.
So keep your eyes open, they are out there.
My biggest problem is I've got finish some of the projects that keep distracting me so I can sit down and learn to use these tools.
Joe