Kirban (
www.kirbanperformance.com) is or was selling BSM that he said was as close to original as anyone has ever come. As I'm sure you've found, you can't get the original from GM.
Personally, I think the cars look better without it so I left mine off when I painted the car. To each his own, though. Since there's no protection I do have to be extra careful about where I park so I don't get whacked.
Jim