To chrome aluminum, it has to be polished first to have a smooth surface (perhaps not as shiny as a full, heavy duty chrome-like- polish), then is would need to be copper plated, nickle plated and finally chrome plated (usually in multiple layers of each). It's not a cheap process to chrome aluminum.
On the original static hero, I spent days polishing that one to get a near chrome like look. It can be done, and is a lot cheaper than chrome plating. Just needs a lot of elbow grease.
One other note, polishing followed with clear PC or chrome plating might make the parts to thick to fit together properly. I have the parts designed to work as finished - adding additional thickness may cause problems and the saber may not fit back together.