Print with 4 walls @ 215c with PLA for best layer adhesion. 25% infill gyroid.
 

I have tested these to be an extremely precise fit with my ender 3 v2 to some ebay carbon fibre bars, I also made another version fitting to a common ID on aluminum bars, you will find that version with an "ALU" in the file.

The ID for alu is 19.8mm and for carbon its 18.2mm. Make sure to check before fitting, The clearance I left is 0.2mm, if your printer can get cleaner dimensions you can decrease it.