I don't think Proteus would have let any decals or head badges go to kit builders. My first frame was a proteus kit. Their booklet on fame construction was pretty helpful.

The Proteus frames I saw in the '70s were really clean. I never knew anything about the builders though. Most of them had side attach seat stays, but they were more like fastback stays than the wrap around. Proteus
Shows a Proteus headbadge