At the local paint shop where I buy my paint, they have five different shades of my OEM color. This is to account for oxidation, fading, etc.
White is the easiest to match. I'd spend more money on a good fender. I used an aftermarket fender a few years back. It didn't line up for shit, and I dented it just pushing it into position.
So, get an OEM fender, pick the right shade, paint the fender, then buff the car so the shine level is the same all around. A shop can blend it for you too.