Bunnie Huang posted teardowns of the form 1 and form 2.
This picture shows the form 1 galvo assembly (assuming you have form 1) and the text “20K-0098” is visible on the motor - not sure if it is x- or y-axis.
Googling for “20K-0098 galvo” actually returns another thread from the formlabs forum in which another user had similar issues with the y-axis galvo: swapping out a bad galvo: the PhenixTech PT-20K is a drop-in replacement.
Good luck