Outriggers

Aluminum has a higher reflective index (great for polishing) than any other metal ,as long as it's not cast aluminum. If you want them to look like a mirror start with 80 to 120 grit sandpaper and work your way to 2000 grit in intervals of ~approximately 300 grit. You must remove all the pitting. Then get a buffing wheel with a wool pad and start with red rough compound. when mirror like, spray with polyurethane with a very good UV protector.

Or after sanding to 2000 grit , take them to be triple chrome plated. plating shops will do all the work for $$$$$

They can dip in copper to fill pits ,then sand and repeat until smooth. Then into to Nickle tank, then chrome. left out a few washings in acid and clean deionized water in between the metal applications.

You can polish aluminum to be more reflective than chrome.

Yes, you can polish aluminum to be more reflective than chrome, but on a set of outriggers you'd have a million hours doing so. Not exactly what the OP seems to be looking for. He seems to be looking for a way to clean them up while saving as much anodizing as possible and without a ton of labor.

Once you remove the anodizing the mill finish aluminum will corrode and pit quickly, would have to re-anodized to last. I have worked on a few sets trying to remove the oxidation without much improvement. Rupp alumaguard will instantly make them look good but doesn't last very long depending on weather. Corrossion X on the fittings and fasteners will last for awhile. If you can drop your riggers at the dock without removing, the alumaguard is quick and easy. Corrossion X HD metal protectant would last a lot longer, they also make the Rejex polymer coating mentioned previously.

Perhaps after you polish them up with the various metal compounds suggeseted and or sanding , in stead of wax to keep up the shine try that stuff from SAMs marine supply ; Morton flexible impact primer in clear . Hatteras used that over their aluminum window frames etc. give them a call see what they say at SAMs it might work and hold the shine for a long time .

A search showed a lot of products for aluminum. Some are very labor intensive that requires stripping to bare metal. A set of triple spreader riggers would require a lot of hours to de-rig, strip, refinish, and re-rig. I would compare the cost to refinish vs new (or like new used). Also, not sure if these coatings to refinish will last like anodizing. A anodized set of riggers can last indefinitely if maintained properly.
https://www.saf.com/how-to-specify/how-to-decide-between-anodizing-painting-and-powder-coating/

Have dealt with inherited heavy oxidation on multiple boat outriggers. There are a couple options, protect them with wax so they don't get worse and deal with the way they look. OR, if you want them shiny again, you have to compound the oxidation off which takes the anodizing off with it, then ceramic coat them. It's a lot of work, heavy cutting compound or high grit sand paper required, then has to be properly prepped for the ceramic coating. A good coating will get you a few years of use before it needs to be redone.