After getting my Bambulab x1cc, I had no way to use my larger spools, so I decided to build my own.
The pictured spool has the width of a 2kg Prusament spool and the diameter of a Extrudr 2.3/2.5kg spool.
To build this spoolholder you need the following (besides a bunch of filament and time to print it):
The author marked this model as their own original creation.