Does anyone have a trustworthy car mechanic in Orange County, CA?

My daughter lives in the city of Orange, and I am in Northern California. She is a college freshman, I am having serious financial difficulties, and her car needs a catalytic converter. She was told this by a place that does smog checks and her car did not pass. He also told her that there are two kinds of catalytic converters, one that would cost her roughly a grand, and the other about $250.00, and that hers was the cheaper one. Now we need to find a trustworthy affordable mechanic who won't rip her off. You know how finding a good mechanic can be very difficult, especiall for a woman, who get cheated way more than men by mechanics. So, since we need to find a place for her to take her car (Toyota Corolla) RIGHT NOW, I'm hoping someone out there will truly know of a good, honest auto mechanic...thanks in advance..