I suggest that you reference the Sea Cure mouthpiece website. They make an assortment of different sizes to fit practically any regulator. From the list given for size number 1, you can see the multiple regulators that use mouthpieces that will fit the 109 and 108. From that list, you should be able to see a model which is still produced. From that point, you can then purchase a mouthpiece made for that model.
I really like the ComfoBite mouthpiece, as well. I use them on my Atomic regulators.
I have several NOS Voit mouthpieces that still have the release agent on them. They will fit the 109, but may not be the style you are looking for. If you’d like one or two, let me know.
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