I've been using this box advertised as being for shotgun shells, 18650s fit a bit loosely but it works well. this specific one is designed for 10 or 12 gauge 3.5" long shells. A box for 3" 12ga shells would give an even nicer fit, with the taller box the cells seem like they could almost fall out of the organizing section and get jumbled up, because the "walls" only go about halfway up.
TL;DR look for shotshell boxes on amazon, should give you more options
edit: just realized this post is 2 months old, oops
I can't include every vendor's name, there are just too many so hopefully that sizing photo will help you. I haven't included Sixteen92's 2ml sample in a case because I just put mine in the side of the Plano 12 or 16 Gauge box.
BPAL's imps are also 1ml. BPAL full size fits, tight into a 10-12 gauge ammo case.
For 1ml vials (BPAL Imps, Solstice Scent samples, etc) THIS case works perfect. (Search Amazon: MTM 38/357 Cal 100 Round Flip-Top Ammo Box)
For full size bottles (BPAL, Madame Josephine Rollerballs, Solstice Scents full size roller balls) THIS case works. (Search Amazon: MTM 25-Round Magnum Shotshell Box)
For Cocoa Pink drams, Smelly Yeti samples, Alchimia Apothecary samples, ThreeTenLabs samples, etc. THIS case works (Search Amazon: Plano Shot Shell Box, 12 & 16 gauge)
I hope this helps! :)