You can find the Shiv Puran in Odia (ଶିବ ପୁରାଣ) PDF for free, primarily hosted on the Internet Archive, which offers various editions and translations, including the Gitapress version. Best Sources for Odia Shiv Puran PDF

The Government of Odisha has digitized many rare manuscripts. Websites like the Odisha Virtual Academy sometimes host literary works in Odia.

While finding a free requires patience and careful searching, the safest and most respectful route remains either downloading public-domain scans from Archive.org or purchasing a digital copy from a verified Odia bookstore.