Paint your preferred bars silver in center where exposed.

Or, wrap tape all the way to the stem.

Or, quit worrying about minor things that you cannot change easily.

A quick check of QBP inventory shows:
249 black bars
23 silver bars

This includes all iterations of width, drop, reach, etc.

So, only ~ 1/11 bars sold is silver - and none are what you want.

Actually, this might work for you:

http://www.ritcheylogic.com/dyn_prodfamily.php?k=394053

It is possible to remove most/all of the anodized coating by soaking in mild sodium hydoxide solution, plus scrubbing with steel wool. Question then is, do you want to trust a bar you soaked in lye and removed some material with steel wool, just so it'll be silver?