Any shell will work since it's just a cover, no need to attach any of the loops that some shells have, those are just more trouble than anything, just use the belt/closure the shell has and you're good to go. Just be aware, collecting shells can be addicting 😅 I've lost track of how many I've had over the years, they're much cheaper than buying new pants so it's easier to match teams you're on. In my experience, the PP90/PP9K shells run a touch longer, Warrior girdle shells run smaller (the ones from the past year or so are really small), the Tacks shell is a bit more fitted but has a zipper at the waist to add length if need be. Bauer has some Supreme shells, they're pretty true to size but I always felt they seemed cheap, the material on the backs of legs was thin and like mesh, I wasn't a fan. You can also use pant shells, they tend to run a little larger, a PP10 or the Bauer pant shells would prob be good since they're a little longer than a regular girdle shell, only other difference is they don't go above the waist/belt where as a girdle shell will go higher.