I’ve been using home made molds for years. You can make a follower quite easily with a plastic cutting board and a jigsaw. Use the white plastic kind. I’m not sure what they are called commercially, but they are made of UHMW plastic (Ultra High Molecular Weight). That is what we use in the food industry. I am currently using a follower made of 3/4” plywood and several thicknesses of polyurethane. Some will probably find fault with that as a sealer; but I have no problems with it.
This discussion brings up another question: I’ve frequently thought of making a square mold - it would make a square “wheel,” and I’ve heard jokes about square wheels elsewhere; but it would be quite convenient for slicing purposes. Have any of you ever tried novel shapes of molds?