Hello,

All of the glass gauges have been sold.  Thanks for inquiring.

As for mouthpiece cleaning, all I deal with are hard rubber 
mouthpieces.  For my own purposes, I just use a swab perhaps once or 
twice a week (I do pretty heavy playing).  I suppose running the 
swab through will change the interior over time, but I make enough 
mouthpieces for myself and make subtle changes often enough that I 
have not had a problem.  

A friend has suggested one part lemon juice, 10 parts water for a  
cleaning solution.  I used this once with no rubber discoloration.

Omar Henderson, at Doctor's Products (http://www.doctorsprod.com/) 
carries mouthpiece cleaner as well.  Omar is a scientist at the CDC, 
and all of his products are environmentally friendly, and/or 
scientifically tested.  I recommend them.

I hope all are well.

Ben