It appears to me that the extract of liquorice (glycyrrhizic acid) is a strong anti-androgen; one could possibly use instead of RU for it is a lot cheaper. Not sure if the potassium salt thereof is effective, since it is available in its pure form and also water soluble and therefore easy to handle. Also there is chaparall (larrea tridentata) extract (NDGA), a CRTH2 antagonist.