The best replacement for sheath is shift dress.

The best alternatives to sheath are rated as following:
★★★★★  shift dress
★★★★  scabbard
★★★  sheathe
★★★  shift
★★  a-line
★★  sheaf
★  introducer
  armor polish
  axon
  schwann cells
  linea alba
  joint capsule
  kydex
  nylon sheath
  neurilemma
  femoral canal

Your alternative for sheath is not listed? Suggest!
Speaking about sheath, one probably shouldn't forget about sharpener.

Other search terms related to sheath and their ratings are:
★★★★★ sharpener
★★★ double knives
★★ obturator
★ sword
You have in mind a companion for sheath and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of sheath in all years. Click on graph for more.
sheath
shift dress
scabbard