Have you considering making them yourself? I was surprised how cheap 3d printers are now a days. You could get a Prusa Mini for $350 or a Creality Ender 3 V2 for about $269 and the print quality is amazing from either. I just picked up my first printer (Artillery Sidewinder X1) and the learning curve is not nearly as bad as I thought it would be. Go to thingiverse and look up Hanna and you can check out all the cases they have and it's all free. You can take those STL files and import them into Blender (pretty complicated software) or Tinkercad (much easier to use, but not really powerful) and edit them however you want. I made the Hanna ones as well as a drying rack for cuvettes and they came out great. if you would like more info just let me know.
