It is large. There are great numbers of unpublished specimens of several of the Jehol Group taxa (Caudipteryx, Microraptor, etc.) in Chinese collections.
In 2006, I saw plenty of unpublished specimens of *Microraptor* and possibly other deinonychosaurs... most of them on display in museums. I get the impression new specimens are only published if they can be claimed to be new taxa or if the previously described specimen (singular!) of that taxon is much less complete.