I bought a few metres of silicone wires from aliexpress and it came without a spool. So I just draw something and print. This spool can hold about 10-20 metres of 22awg silicone wire. It should work for PVC wire as well. The spool dimensions are 60mm diameter and 32mm height.

Each spool contains 10 metres of 22awg silicone wire, except for the top right is 4x 5 metres of 24awg silicone wire.