A $1.48 goes a long way... Black Battery Cover!

[xweaponx]

I think I am going to get the red dye. I have a killer red theme that would really set off with a matching battery cover...

You could also mix dyes to create other colors. I think Wal-mart has:
Black
Blue
Navy Blue
Red

Michaels, Hobby Lobby or other craft stores might have a larger variety such as orange, brown, etc. The dye I used and works well is basic fabric dye...