Where to buy small eddy current brake?

If you only need one, try some second hand shops for an old recodr player. One with a synchronous motor.

If you apply DC to the coil it will act as an eddy current brake. I don't know just how much current you'll need but you will need ALOT less than 120 volts to do it. That much DC voltage will cook it.

JURB

Actually pretty much any induction motor can work as a brake, if you put DC through the windings. Of course all of the mechanical power (and the electrical power from the DC supply) will end up as heat inside the motor, so be careful not to cook it. Most of the mechanical power will end up heating the rotor. If you are getting rid of a lot of power and the RPMs are too low for the motor's own fan to be effective then consider adding a blower to force air through the motor.

Chris