There were two Cello Cartridges.
The Maestro is an Ikeda and it had a rounded front, straight sides and flat back. The stylus is like that of a Decca cartridge with no cantilever.
The Chorale is a Miyabi. It's round and it has the conventional cantilever type stylus assembly. This cartridge is not typical as far as loading goes and you may find that it sounds better when loaded with something between 100 and 1000 ohms.
The Maestro needs the right arm and knowhow in setup or you won't hear what it can do. The Asian audiophiles seem to be the experts on these.
The Chorale will work in more arms and it's not uncommon for it to be a low rider. After 20 to 50 hours of use the cantilever ususally ends up closer to the cartridge body and you need to adjust the VTA.
Both are very good cartridges in the right setup.
New Ikeda and Miyabi Cartridges are in the thousands but the used market for a Cello Cartridge may bring around $700-900 unless you find the "right buyer."
Used cartridges are a gamble and unless it's a one owner item with believable history and a highly rated seller a potential buyer will be more cautious.