Looks like the parts store, is trying to sell as many parts as possible. Imagine that.I've replaced two calipers on vehicles that I've/we've owned, ever. That's a couple dozen vehicles, probably between million and million and a half miles total.
Calipers are not wear items and do not normally need replaced. The exceptions might be for a vehicle up north that is exposed to considerable salt contamination, being in an accident or having a million abusive miles on them and the seals are deteriorated.
Are her brakes making noise or is her steering wheel pulsating when she applies the brakes? If not, there is a very good chance the vehicle only needs pads, probably just the front as 60-80% of the braking is accomplished by the front brakes pads and they usually see the most wear.
If she wants, she can come by the house Saturday morning and I can pull a front and rear wheel to inspect the brakes. Then she can order the parts she needs. I’m just south of Claremore.