Who do I ask for a reference after a layoff?

My manager was laid off too and I am unsure who to use as a reference. I do not usually post, so bear with me. A colleague offered to vouch for me. Is a client acceptable?

I kept a note of my results so my references could be specific. They appreciated it.

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