Some full text measurements can be found in the ERIC database. ERIC has two types of materials: documents (such as books, manuals and pamphlets which have an identifying numver staring with ED) and journal articles (which are not in full text unless available in one of the library's subscription databases). Documents with identifying numbers starting with ED can be found in full text either online or, if it is an older item, through interlibrary loan.
Some ERIC documents contain full text instuments in the document's appendix section. The ERIC onlline database advanced search screen has a limiter that you can set to search for douments that have full text tests and measures.