Thank you all for the advice. fhassm, I agree I should be able to find it in a non-specific application, but no luck yet. Thank you for the link!
But I found this interesting link - someone has already designed a replacement gear in Thingiverse.
The gear is for the iRobot roomba, but the Eufy is essentially a copy of that and i think the gear is the same.
Since we have a 3D printer at my work, I figure no harm in trying! Plus it will be fun to try and fix it with a 3D printer object.
And yes, Das Boot is one of the all-time greats, along with FMJ. You have good taste in films!