You may find that as with all things the spec will be a compromise of what you want and what you can get .
First , if anyone says ''aircraft grade'' move on. A generally spurious term meaning very little of importance.
6082T6 is a good compromise of all the qualities you require . It will anneal and work harden back to a decent strength but design should negate the needwhere you can, it's available in thin gague (get the thinnest that you can) and it's cheap as chips compared to some other options .
You will need to design the stiffness of the part into it with flutes, folds and ribs , if you use sheet that's thick enough to do without you will never bend it succesfully without an industrial press. Light aircraft use 6061T6 because it's available down to 35 thou thickness , has reasonable workability and reasonable corrosion resistance ,is fairly strong , but not the best in any of those qualities.
Auminium warehouse at Wellham Green Hatfield do a cut to size service and are good to deal with , no connection just a happy repeat customer.