The best replacement for lead screw is ball screw.

The best alternatives to lead screw are rated as following:
★★★★★  ball screw
★★★  threaded rod
★★★  rack and pinion
★★★  belt
★★  timing belt
  belt drive

Your alternative for lead screw is not listed? Suggest!
Speaking about lead screw, one probably shouldn't forget about stepper motor.

Other search terms related to lead screw and their ratings are:
★★★★★ stepper motor
You have in mind a companion for lead screw and it is not yet here? Propose!



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lead screw
ball screw
threaded rod