It is found in little pockets at the peaks of the Experience Mountains, and is also produced in the Forest of Belief by the diaphanous entities who float through the forest's systems undisturbed by anyone,. They have no enemies or resistance and their joy is in simple perception. These beings, known as the Conscious One (they have no word for selves in their language) distill Explorer's Courage from the brows of their maidens in a ceremony called Coming of Knowing.
Small vials of it have been exported to other species who have gone through long searches to find it. To buy it is impossible; but with enough perseverance you can find someone representing the One who will give it to you in exchange for an oath: that you will use it to broaden the integration of awareness in every plane, and that you will pass it on to another of equal virtue, in exchange for a similar oath, when it has done its work for you. This is necessary because it has a remarkable capacity to bring any individual up to a permanent level of high resonance at which point the fluid itself is no longer needed, and can be passed on.
The virtue prerequisite is necessary for the preservation of the species. Beings lacking it who have somehow come upon Explorer's Courage are rattled to death by fits of denial and rationale. Therefore the One are careful to qualify the seekers to whom they will surrender it. I have been told you are so qualified; but that will be clearly evident shortly in any case.