It sounds like an automation-quality linear actuator would work; I've used them for Z axes before. You can often find them used or surplus with motors on them nobody can figure out. They often have dual high-quality rails and ball screws inside, mounted in a sturdy extrusion. Look for ones that have precision ball screws inside; some are made as window openers with inferior screws; you also want a relatively fine pitch. Some have sliding-tape barriers to keep chips out. I've generally stripped off the motors and adapted others I understood better. Ebay might be a good source; here's one I just found, for example, (but I don't specifically recommend this particular seller or product):https://www.ebay.com/itm/Linear-ball...sAAOSwffhdZoL4