The Law Library generally has other official state reporters that predate coverage in the regional reporters. Search the catalog by the name of the state and the phrase "law reports." LLMC Digital--a commercial online source to which the Law Library subscribes--contains PDF images of many old state court reports. Follow the link on the Legal Databases & Indexes page. The Caselaw Access Project also provides access to reporters from many state and federal jurisdictions (including Washington) with PDF scans of the original:
Includes reporters covering all fifty states plus federal courts as well as the Northern Mariana Islands, Puerto Rico, some tribal jurisdictions, the Virgin Islands, Guam, and more. Coverage for each jurisdiction varies. Includes PDF scans.