Isidora Forrest, a Priestess of Isis and author of Isis Magic shared the Hor Ostracon which are small hymns of Aset/Isis written in Demotic in a blog post. Here is the link:
Addendum: Isidora has said that she got these from the Archive of Hor by J. D. Ray.
They can also be found in Holger Kockelmann’s book Praising the Goddess: A Comparative and Annotated Re-Edition of Six Demotic Hymns and Praises Addressed to Isis. de Gruyter, 2008, p. 13-14.