expresso pot restoration?????
If it's aluminum, aluminum loses its sheen - if you like permanent shiny enough to spend $$ for it, you can get a stainless steel mokka pot.
You could polish this one up, but it's going to reoxide anyway and that patina prevents further corrosion to some extent. Unless you so want to end up ill effects, odors, etc, keep any cleanser/plish far away from the interior, or the removable parts. Even only semi-purists like me try to avoid getting even regular soap in there..