Errr, Make Up For Ever palettes, LOL. I got mine from the MUFE boutique in New York. You can call and order them by phone, from the boutique. the number is : (212) 941 9337
nix'ie palettes are just 1mm bigger so you could fit MUFE shadows in them but there will be a tiny space left...
you could also use Yaby freestyle palettes
Yaby Cosmetics makes a blank palette with a gorgeous mirror inside and the palette is white! And inside there are no wells, but it's just one big magnet and you can fit all your depotted eyeshadows of any size inside.
You can also de-well a MAC palette so that the palette is flat and will fit all shapes of shadows. I saw Enkore did a video on this.
Okay I'm back with a (slightly) cheaper alternative that you can get without talking to someone on the phone ( although the MUFE employees are really nice and efficient). This palette has the EXACT same dimensions, looks the same, and if I'd known about it, I'd have gotten these first instead.