Is there a way to get extensions for a busy light or online indicator cord?

YES and YES!!!

You can use the Plantronics OLI Extension cord

(p/n 46429-01). I’ts a miscellaneous item.

This will extend the cord that connects to the busy light.

The cord is 6 feet, this extension will add another 6 feet.

(note this extension will not give the appearance of long luxurious hair)