While I couldn't find a single, reliable English PDF source for "Shams al-Ma'arif," you may be able to access the content through:
For decades, occult scholars, historians of religion, and daring esoteric practitioners have whispered one name with a mixture of reverence and fear: Shams al-Ma'arif al-Kubra (The Sun of Great Knowledge). This 13th-century Arabic grimoire, written by the Algerian Sufi scholar Ahmad al-Buni, is arguably the most powerful—and controversial—book of magical theory in the Islamic world. shams al maarif english pdf exclusive
"The seeker must know that the letter Alif is the pillar of the throne, and he who masters it masters the East and the West..." While I couldn't find a single, reliable English