The society sells (PDF-like) of the Quaderni. Visit the official PLIDA shop online. You pay via credit card or PayPal and receive a download link. The cost is typically €12-€15. This is the most reliable source—you get high-resolution files, answer keys, and often downloadable MP3s for listening.

The PLIDA B2 exam verifies that a candidate can understand complex texts and interact with native speakers with relative ease. Quaderni del PLIDA - NUOVO esame B2 - ALMA Edizioni

: Full "chiavi" (solutions) are included, making it suitable for self-study.