A documentary about the wah pedal? Why not.
You won't find a date, you have to date them by looking at the components. But unfortunately there's nothing really special about a late 80s model like you've got there. Well, except that it's 20+ years old. That's something. The electronic parts do change over time, and that can definitely affect the sound (in a good way or a bad way). It kind of depends on what was used in there.I was looking for a year, but don't see one anymore.