You may find some cheap Chinese "body massage" vibrating devices with adjustable speed settings, probably in pink. You may not want to trust them with any intimate parts, but I've found that they're great at vibrating toner or flour down a paper funnel, so wouldn't be surprised if they also worked for this.
PSA - WARNING
Do NOT attach vibrating things to your skull! This is a very easy way to get a concussion.
Perhaps try taping an electric toothbrush behind your head...
Haha, I held my electric toothbrush behind my ear for about 60 seconds and it worked! The effect lasted only a couple of minutes. It seems like the heavy vibrations mixed things up in there, and when they settled back down, the ringing slowly returned.
I was thinking the same thing! Is buying a massager thing on amazon a similar solution, then just sleeping with it under your pillow?