Sally Jo, another thing to add RE: places to find these clothes: I also came across this list on The Budget Babe about shopping recommendations for finding budget-minded clothes that are stylish and appropriate for women over 50: http://www.thebudgetbabe.com/a.....-Shop.html
My mom has found some great pieces (skirts, blouses, wrap tops) at J Jill and Coldwater Creek. Their retail prices aren't what I would call cheap, but they aren't ridiculously overpriced, and you can often find good coupons or sale items. (I'd stay away from J Jill's outlet store, though - last time we stepped into one, it had totally different selection & quality from the merchandise I'd seen in their stores, and we were unimpressed.)
I saw from your post on the "favorite low priced stores" thread that you're already an experienced consignment shopper. If you have a Nordstrom Rack nearby, you might want to try your thrifting strategy to scour the selection there - if you are impatient (one of my own flaws) it can be overwhelming to sort through overcrowded racks of merchandise, but sometimes you can find the perfect high-quality item for the fraction of the price it was in the store.