Sigma-Aldrich, a major supplier for laboratory chemicals (for professional & University labs) list Chlorohydroquinone (2-Chloro-1,4- dihydroxybenzene) in its catalogue. It's not expensive (100 grams around $25-30) and there's no indication that it is especially toxic or hazardous. So it should be available from different suppliers, at least on special order.(posted 8304 days ago)Regards Georg