The Yashica and Yashica-mat 124s are almost legend for being good buys, and the top end Seagulls are supposed to be pretty good, although I've not used one. The Mamiya C220s and C330s, while good, are large, klunky and heavy.
My suggestion would be that even though she says she wants a "a relatively (but not too) cheap, 'toe in the water' type", she'd likely be pleased with being "pampered" with a nice Rolliecord or Rollieflex. Plus, you're almost assured of getting all of your investment out of it, should she not like the TLR experience.
Never believe exactly what a lady says, if it's humanly (or superhumanly) possible to do better.