Spool holder modified to negate the requirement for a 608 bearing

thingiverse

I originally printed the axels that came with the OP's design, and fitted 608 bearings, but I found they rolled too easily, over-spooling, causing tangles. I edited the file to make the ends the same dimensions to fit into the holders nicely, but with no bearings, so your filament spool has some friction rolling across these axles which don't roll in use.