Having a smallish shaper and using a boring bar/single tool appropriately ground, one could "clean up" the ridges somewhat? It would be tedious and persnickity machine work, but even cutting down the ridges might afford looser disks.
And - along the same lines - simply clean it out and try a "keep on going" attitude?
I've recently seen SEVERAL "clutch paks" for the multidisk - one was NOS which would be the disks of choice.
Joe K