Here is my take on a filament dispensing dry storage environment for hygroscopic filaments.

It was designed so it could be installed above a printer horizontally, have a range of depth adjustment and a (mostly) universal spool holding hub so as to adapt to a range of different spools.

It mainly requires a suitable storage box - it was designed to utilize a Sistema S487 5Ltr "Klip It" Storage Container because of it's size and the lids integral sealing system - but undoubtedly can be adapted for other storage boxs, vertical installation etc.

Other things you will need are;
A couple of the usual 608 skateboard bearings.
A PC4-M6 push fit pneumatic coupler or another alternative filament exit strategy for your material
18 x 10mm m3 machine screws and 6 associated nuts (for the threaded flange and its retaining ring)
A length of PTFE Boden tube to direct the filament to the printer
A suitable drill and bits for cutting the holes required

Use the retaining rings inner dimension to mark the location of the required holes and please be careful - depending on your choice of storage container their materials can be quite brittle and drilling/cutting/sanding needs to be done with low pressure and great care.

The stand off on the base spool holder allows good clearance for the adding of silca gel beads (loose/in a container of your choosing/sachet as rquired). With the silica beads added the relative humidity in the box can be as low as 10%