I know Knight offers plastic wad cups for their in-line shotgun, but those are 12 gauge. When I was really into ML shotgunning, with the 10ga, I had one cabinet that was full of fiber wads, cardboard wads and the wool felt Wonder wads, those worked very well. I first noticed the issue with plastic wads on a goose hunt I was invited to that I was asked to use the 10ga. I cut open 10ga waterfowl shells to use the steel shot and wads for the hunt.
There may be wads for this now, wasn't back when, but haven't looked since I no longer have it.