This is a kit (two plates, one for each axis) for the Multifunction Worktable (BG6300 but also known under multiple different names and readily available on eBay). You will need shaft couplers (5mm to 8mm), standoffs , Nema17 motors, and some additional hardware (M3 screws etc.). Those 3d printed plates should be a direct, bolt-on replacement. They allow for instalation of different bearings so please feel free to experiment.
Planar parts, should print just fine as long the first layer adheres properly to the bed