There are moulded plastic ones with a notch for the cable to sit in. They just clip onto the top tube but don’t have any securing nut/bolt, so can be taken off fairly easily. I’ve only seen them in black. Some lower end completes had them fitted as stock/spec bitd. My Peugeot defo had them.
These are new versions, similar, but not exactly the same as the originals [ Attachment: You are not allowed to view attachments ]