It has been close to a month and I’m sure you are quite busy, but did you find anything out about anyone who might have access to the Mazzeo mechanism to be able to use it for repairs, or a repairman who specializes in Mazzeo models? I’d certainly appreciate it.
Mazzeo model clarinets are a diminishing breed, not likely to be seen again. On the other hand ANY really good woodwind repairman can adjust and fiddle with them. I had a wonderful fellow here, but he died, unfortunately. He also loved all clarinets and especially liked older antique clarinets. He fixed my plain Mazzeo so that it would not have the excessive back push on the A above the staff, if you know what I mean. The repair was quite complicated, but works beautifully.
In Boston, there was a repairman who worked for the Haynes flute company repairing and placing keys on Haynes flutes who was wonderful with them. There are no specializers in Mazzeos … just really excellent interested people.
Do NOT think of this instrument as some arcane weird thing. It is not. Long ago I used to play full Boehm Mazzeos … as a matter of fact, they were a set of Rosario’s. They seemed complicated, but really they are not and I played them through the routine of a principal clarinetist in a major symphony orchestra with very few, if any repairs that I remember. But I DO remember looking for reeds. THAT was ghastly.
Let me know specifically what you want. The Mazzeo mechanism is relatively simple. A spring opens the third trill key on the right each time you put the right hand down, and/or the second and/or third fingers of the left. If you add the “a” key to this you have the throat Bb. That’s all. Period. This is a matter of tightening and/or loosening two wire springs so that they balance and open the trill key all the way and close it when you lift the fingers. Understanding that concept is all a repairperson needs to know. I suggest you find your favorite repairperson and show them the problem or the mechanism. These people are frequently in the business because they like to mess with this kind of thing. You may find yourself a master and personal Mazzeo repairperson this way.
Best of luck to you. Hope I have been of some help. The mechanism is simply a further refinement of the clarinet.