Please consider selling whatever that special-Ilford/Harman-proprietary-chemical is so we can scratch mix up own own cold tone developer! It seems like such a travesty that this "eye of newt, and toe of frog" shall sit for thy eternity in the confines of a commercial laboratory whilst the masses scorn the injustice of said eternal confinement.
I believe it was a specialty chemical made just for this developer. It is not therefore not sitting on any shelf in any lab. Making custom molecules is not cheap.