I echo Ken's request.
I did find in the Citizens & Business file at the National Archives invoices from Richmond's Watkins & Ficklin, who were dry goods dealers, for the blue and "rich pink silk" used for the first 120 ANV silk battle flags of November, 1861. These flags were not red as red back then was a trim color for collars, bodices and cuffs and thus not available in bolts width enough (18 inches) to make flags. Pink or rose silk was, hence these flags being that color.
I would suspect that the yellow was for some of the trim for these flags (most had that - one grouping had fringe) and the green was for the CS hospital flags (Federal flags for them were yellow).
Are the invoices you are finding signed by officers of the Richmond Depot like William Cabell or Colin M. Selph?