I see that you are located in the Research Triangle in NC. Does she live there also? There must be tons of jobs for admin. assistants at UNC, Duke, etc. Universities have fairly uniform HR rules on benefits, such as 403(b) participation/matching (nonprofit version of the 401k). Plus they are very strict on Dept. of Labor regs -- so no age discrimination is allowed, at least overtly. If she lives elsewhere, she can likely find similar college/university opportunities locally.
She might consider springing for a complete makeover -- hair (including coloring), makeup, work clothes, so that she appears 10 years younger. Perhaps she could hire a professional consultant on this stuff and who would also help get her prepped for the job hunt. It would be worthwhile investment. Also, if she can hide her age on the resume -- this might help; but it is a often-used tactic and can be identified usually.
I took a quick look at the non-faculty/non professional jobs at UNC/Chapel Hill just now and found quite a few jobs she might be qualified for. For example, this one:
https://unc.peopleadmin.com/postings/138291
It's permanent, normal business hours, working in the school of nursing supporting an assistant dean, and has a salary band of $38,988 - $50,173, with minimum only of a high school diploma (or equivalent) and one year working in an office. There are many managers who would value a mature employee who can demonstrate the gold standard qualities of always showing up on time, being proactive (looking for ways to make his/her boss's job easier), highly professional, upbeat & positive attitude, and strictly focused on the job all day.
I saw on the UNC jobs page that there are temporary positions also available. These are an obvious potential door to a permanent job.
By the way, one excellent strategy would be for her to look at the directories of staff at some of these institutions, locate the admin. assistant -- usually shown by name and contact info in the office listing for the head person, and call him/her and ask for an information interview. Say that she is wants to work at (institution name here) in a similar role and would love a chance to ask a few questions. Perhaps over a coffee.
The large institutions are the way to go, in my mind. But you have to really work at it to find the jobs and apply for them. Hope this helps.
-BB