Basic Certificates - adding more details from course

After completing my courses, my students need to use a certificate as proof of completion to get professional Continuing Education Units (CEUs) each year. Each course gives them a different number of CEUs and I need to be able to include this on their certificate.

I could use the course category to store the CEUs for each course, but don't see a way to output that to the certificate.

Is there a code for course category for output? Are there other codes that can be added to the Basic Certificate in Settings, apart from: FIRST_NAME, LAST_NAME, COURSE_NAME, COMPLETION_DATE, CERTIFICATE_NUMBER, UNIT_LIST?