I doubt you will have any issues using the taper wall Remington wads in a straight walled case w/the proviso that they seal/expand well enough at the forcing cone that you don't experience bloopers. I've had the experience were some wads did not, but it involved long or opened forcing cones or overly large diameter bores. If your bores, chambers and forcing cones are unmodified I doubt it would be an issue. Just saying.
If you are worried about powder migration, just apply some pressure to the wad when its being loaded/seated and be sure you have a tight crimp. As mentioned earlier, the powder granule size can make a difference, but flake powders lend themselves to staying put w/a bit of wad pressure and a tight crimp. At least that's been my experience. Plastic wads may require no pressure, but it does not mean you can't apply some anyway.
I'd try that first before going to any added bother.
If you really wanted to go to the trouble you could make a hand held forming tool like an old time soldering iron with the head being a cylindrical piece of copper and the end having a conical taper on it so that it would expand the skirt a few thousandths of an inch. Heat it in a pan of boiling water as you will not need a lot of heat to form an expanded diameter on the wad's skirt.
Original Ljutic Mono-Wads were simply plugs cut from some type of fibre board. You can fabricate a wad cutter by taking a piece of tubing that has the correct inside dia. for your desired wad diameter and simply grinding a chamfer on its outer side, so that you form a cutting edge on one end. With a block of wood for backing and a mallet for driving it, you are in business. Stick its cutting end in some paraffin wax for lubricant and it goes better and after a while you are almost producing waxed wads. They are also easier to push out of the wad cutter. Use a wooden down for that. Just some thoughts; perhaps something of use to you. The punches that one can buy are known by the name of arch punches.
