They were standard on Belvedere IIs, unless it had the Silver Special package. Many repainted cars are missing them, it is easier to fill the holes and paint over than restore the annodized aluminum trim.
GTXs, Satellites or Belvedere Is didn't get the upper sider moulding.
I'm not a '67 guru but I do have a '67 Belvedere II and I slept in a Holiday Inn Express last night.