Shaykh Asrar’s works are often listed on Amazon Kindle. While these are not standard PDFs (they are .mobi or .azw files), they can be read on any smartphone with the Kindle app. This is often cheaper than the paperback.
If you are specifically looking for PDF versions or digital formats for research or convenience:
“I’m looking for legitimate PDF copies of books by Shaykh Asrar Rashid, such as The Restoration of Sunnī Belief or The Islamic Response to Imperial Hubris . Does anyone know if official eBook versions are available for purchase? I’d prefer to buy or borrow legally rather than use unauthorized scans. Jazakallah khayr.”