In the early days of the Commando program, N-V bought their clutch and brake cables from a small manufacturer in the West Country of England (or maybe South Wales). His design had Teflon-lined outer cables and graphite-impregnated inner cables. You could tie a knot in the assembly and it still worked smoothly. They never needed lubricatiion. They were first used on the works racing and moto-cross bikes and the prototype Commandos.
I don't know if that particular manufacturer survived as production ramped up. His "facility" was three hen-cabins in a farm field (I think it was the man's farm), and N-V sent a van down to collect the finished product every few weeks.