The choice between NEMA 17 and NEMA 23 depends on your printer’s frame, size, and the level of torque you need. Most consumer 3D printers use NEMA 17 because they’re compact, energy-efficient, and provide enough torque for standard applications. However, if you're building a large-format or high-speed printer, NEMA 23 could offer more power—just keep in mind that they require stronger drivers and a compatible power supply. What kind of printer are you rebuilding, and what improvements are you looking for? In the past given low cost printers I have used this Anycubic printer which is $229 on Amazon https://www.amazon.com/ANYCUBIC-Printing-Engraving-Filament-Auxiliary/dp/B089M178BG  I like this printer due to the fact it comes mostly assembled and all that is needed it to attach the head rail and plug in the motors and controller.  It also has a glass bed as well as dual elevation Z height screws and dual bed rails. Recently I invested in a Bambu Labs Carbon X1 which has performed flawlessly with much greater quality than anything I have used in the past. Hope that helps.