Yup. That looks like it. I bought one for my dad's Camry. They only had it for 2003 model years and older last summer. Although I heard from people here on PC that the Classic Prius use the exact same size as the current ones. I've already washed/dried mine once last March and they were really dirty after 8 months. Now it's 12 months and I'd like to see how it looks like. They're better than Toyota ones cause they're particulate filters vs. Toyota's 'dust & pollen' filter.
Bought a new one for my dad's Camry. They still don't have the new Prius' air filter so it looks like we might have to use the Classic's part no.