"A research instrument is a testing device for measuring a given phenomenon, such as a paper and pencil test, a questionnaire, an interview, a research tool, or a set of guidelines for observation."
Mosby's Dictionary of Medicine, Nursing & Health Professions
Try searching Dissertations and Theses Global for the instrument if you have the name for it. It sometimes has the complete instrument in the appendix
What is the difference between a "published" and an "unpublished" test/research instrument?