Does the "plunger" type cherry-pitter work?
I actually just pitted about 10 gallons of cherries using a plunger style pitter very similar to that one.

The cherries are gravity fed from the hopper into the chute. Only one cherry can fit at the bottom of the chute and it lines up nicely with the plunger.

From time to time cherries would fail to fall into the chute and I would have to clear the traffic jam. The majority of the time they fell in just fine and I could pit about a cherry a second.

The plunger does not have to line up with the top of the cherry, it will eject the pit from any orientation. Manual pitters do make for more attractive presentation because you can pick the exit wound location. I used a metal straw to good effect but it was just too slow to pit in bulk.