My dayjob involves designing similar looking aluminium parts and we use commercial anodization service from other supplier. Fortunately I can slip the LDC in same the box without anyone wondering what the heck is that. 😆
I like to sandblast the surface before anodization. We also have small sandblasting cabin in our company. You put the parts inside and push your hands into the heavy gloves integrated to the wall. Grapb small sandblasting nozzle and brush the parts while looking through cabin window. Sand is actually very fine metal particles or small glass grain. It basicly just breaks / modifies the surface without removing material. The surface will then have nice matte finish and will look “factory made” after anodization.
I read about home anodization and it seemed pretty simple. That would be nice to try out sometime. Especially with different colors. Our suplier only has standard black, red, blue and natural silver colors.