I stumbled across a reference to a set of records maintained by the New York Public Library’s Manuscripts Division. The library has approximately 33 boxes of materials from the Women’s Action Coalition:
The Women’s Action Coalition Records trace the rise and fall of a direct-action group often considered part of the “Third Wave” of feminism in the early 1990s. The records are almost entirely those of WAC New York, although there are files on the activities of WAC Boston and scattered files about other chapters. The records contain administrative files, committee files, subject files, photographs, printed material, video recordings, as well as posters, placards, banners, and props used during protest demonstrations.
The finding guide is here.