Martin Maurer is being helpful. He gave me the contact info for the two companies, Binci and Cagnoni, that made reeds for the instrument. Binci said they don’t make reeds for vibrandoneon, and Cagnoni didn’t respond to several emails.
Martin emailed me just the other day to say that he could obtain a complete replacement set, plus duplicates of the ones I already need, but the price he quoted is pretty steep. I’m working out if I can fund that now. He’s been superb in terms of communication and sharing information. Thanks again for the suggestion.