Any stepper (or any other kind of motor) can be closed loop with the addition of an encoder and a suitable driver. At that size there are plenty of options, including all-in-one servo systems, some that even have on-board motion control, ranging from cheap eBay stuff to components that are used in real CNC machines with eye watering price tags.
You mention reliability in the same sentence as accuracy, but accuracy, reliability, precision, and repeatability are all different but equally important parameters for things like CNC machines, and they're only partially dependent on the motor. The mechanics of the machine are as important or even more. What sort or specs are you after?