99NEC Article 321 — Messenger Supported Wiring 321-1. …exposed wiring… to support insulated conductors by…: (2) A messenger with a field-installed lashing material for conductor support.
Not aware of 4-insulated-conductor construction, but based on referenced text, it may be possible to make or modify existing product [like original ‘quadruplex.’] Custom made in suitable quantities through a wire house may be cost effective.
