Ah! The "Tanagraie"!!
These statuets are supposed to reperesent wealthy upper class ladies
Yellow, Green and fine brown were available. but red is a possibility because in the Acropolis Museum that has traces of red color over a "brownish" base.
There even could be paterns and motif on the cloth.
the "black faced" pottery that they have in the Antikensammlung can give you a good idea.
Hope it helps
Kind regards