@LadyDi, As Markku says I can reproduce a very similar thing to the Widex zen, it really is a very simple random tone generator with a few sounds. If I had to put a realistic value on it I would say it should retail at no more than $100. Nothing you can't do with an Mp3 player and comfortable earphones. I use Airdrives, they sit on top of your ears so don't block any external sound. Sound isn't great but they're ideal for listening to masking sounds. But you really have to use whatever you find most comfortable to wear and listen to.
If you can tell me the frequency of your T and what sort of sounds you find soothing and pleasant I'll work some sounds up for you.
I'm not 100% what principle Neuromonics treatment works on, but if I find out I can replicate that too.