Anodizing will take to aluminium but, as with most things, preparation is key. All paint or powder will require removal first - chemical removal will be favourite here as blasting will leave a pitted surface. Anodizing is basically adding a sacrificial corrosive layer on the metal, it's very thin so any and all imperfections will show once done. Much diamond cutting / sanding / polishing before anodizing will improve the finished result. Don't expect this to be quick or, therefore, cheap.
A reliable painter or powder coaters will be able to match your gold forks for a much cheaper result, each has their benefits and down sides. As usual, it comes down to how much you want to work you want to put in yourself or pay to have done....