Solid Aluminium Sheets Alloy

let me introduce myself, i am tahir XXXXXX the position of sr sales executive at XXXXXXXXX.
presently we have a huge requirement approximately 700mt for mill finish solid aluminium sheet in standard sheet size (1220mm x 2440mm x 4mm thickness).
we are looking for the alloy (3000 5000 7000 8000 series) which is suitable for anodizing with better results for atleast 15 years duration without any appearance of stains or any other problems after anodizing.
waiting for your positive reply with y