A prudent strategy before, but also after Integral actually gets underway...
Would be to try to proliferate and promote it, as much as possible, among known far leftists/libertarian socialists, anarchists most of all, and their groups.
The spirit and aspirations of Integral, as presented so far are, at a minimum, pretty kindred and adjacent to them - anti-hierarchy, anti-state, anti-capitalism and the list goes on...
Some differences most certainly do exist, especially in terms of high-end theory and even some foundational premises, but overall, I think it's among that sort of population that Integral, for a start, might find its most willing and critical participants.