I printed this in three parts. It is tailored to fit a certain lab vial that my friend had available. The other designs didn't suit me, so I made my own. You print it in three parts, each nests in the one below it. Height is adjustable and sanding the central column ensures a perfect fit.

I have trouble importing from Blender to Cura and keeping an accurate. I scaled the base proportionally to an x & y size of 63.5mm, you may want to start a test print to make sure that it slides into your can. The upper layers were printed at 62.5mm for x & y. A little sanding and they plugged right together. It goes in and out with a little jiggling.

I have the printer software add a support structure under the print. It pulled away very easily with minimal cleanup.

If I were to continue developing this, I may modify it so that it has embedded magnets so that it clicks into place inside the can. Also, some way to get the vials to lock in may help. As it is, they just sit there loosely.