Installing the second Z axis on a Creality Ender 3 3D p

Hey.
The archive consists of:
- 3 source files in Autodesk Inventor (.ipt) format (left and right Z-axis plate and tensioner)
- 3 folders with STL files for printing with miscalculation of different plastic shrinkages from 0.1 to 0.3 mm, that is, if you use for example PLA plastic with 0.1 mm internal shrinkage, select files from the folder (STL files with shrinkage of 0.1 mm)
Where can I BUY ACCESSORIES !!!!!

For Z-axis Sync, the kit price is $ 20:
Bearing 608ZZ (2pcs) $ 0.92 http://ali.pub/3sil0f
Pulley GT2 (20T W6 B8) (2pcs) $ 3.12 http://ali.pub/3silrg
Pulley 20T W6 B5 With T (1pc) 1 $ http://ali.pub/3sinmc
Screw T8 + nut (Lead 8mm) 400mm $ 6.22 http://ali.pub/3sim4h
2GT closed belt (650mm) $ 2.2 http://ali.pub/3simqu
Z-axis latch (1 pc.) $ 0.46 http://ali.pub/3sin0k
T-nut 20 Series M4 (8pcs) $ 0.83 http://ali.pub/3sinao
Z-axis carriage (1 pc.) $ 4.99 http://ali.pub/3siny0