References when my manager was laid off too

My manager was laid off too and I am unsure who to use as a reference. I have read a lot of threads here and could not find my exact situation. I have one former client who liked my work. Is a client acceptable?

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

Keep everything in writing and save the confirmation numbers. It made the follow-up calls so much easier.