This is a spool holder that I designed. It is completely modular and can be as long or has short as you want. I designed the holes to fit ¾ ID PVC Pipe which can be found at any home improvement store. The actual size of the hole in the print is 26.6mm so anything with a diameter of that size or slightly smaller should work. 

Main Print Settings I Used: 

Filament - PLA

Supports: None

Infill: 20%