If budgeting for a CasaXPS license is absolutely impossible for your current project, consider using open-source or free alternatives actively maintained by the scientific community:

Before you risk your system, check if you already have access through these legal channels: CasaXPS - XPS Analysis Software

Instead, I suggest exploring legitimate options:

Casaxps is a powerful XPS software that allows users to create, edit, and convert XPS documents with ease. The software offers a range of features, including XPS to PDF conversion, XPS editing, and XPS merging. With its intuitive interface and robust functionality, Casaxps has become a go-to solution for individuals and businesses working with XPS files.