References when my manager was laid off too after 13 years as a school bus driver

My manager was laid off too and I am unsure who to use as a reference. This is my first time dealing with any of this. A colleague offered to vouch for me. How do you ask politely?

Use a professional network to find a former manager. Many will still write a note.

Ask former colleagues and supervisors in a short message and give them a summary of the job you are applying for.