I believe a ONI id could work, if it was modeled after the KPT id for example.
Doesn't need to have bases or npcs like LSF, just some liberty to explore other topics of Gallic military and intelligence that the GRN can't really do, since they're "busy" with a lot of front lines.
Could be the ones exploring the link/relations with Rheinland, gathering intelligence in the Omicrons regarding the Outcasts (and finding other troubles too, nomad infected gallic intelligence agents?).
If the other houses have them, and are used with reasonable frequency, as faction groups, individuals, or individuals representing whole groups, why not giving the chance for Gallic players to develop the house intelligence branch.