For sale is one set of change gears for 7x10, 7x12 and other mini lathe sizes, commonly sold by harbor freight (central machinery), grizzly and others. This gear is made from plastic and is much stronger than the solid, brittle original plastic gears these machines come with.
I have been using these gears in my own mini lathe with no problems.
Gears come in Black. And are also identified with the tooth number.
Inner diameter: 12mm (.472")
Thickness: 8mm (.315")