The difficulty is the age, since no Chinese Health Insurance sponsor by an employer will accept you in their rolls after you are 65 years old, and without insurance you can not work.

But I do know a few (one is 87 years of age), who still do work because they maintain coverage with an international health insurance company accepted in China, but expensive do.

And by the way, Medicare/Medicaid is not an acceptable solution because chinese officials do know it will not cover you while in China.