Loud Engine Noise problems of the 2007 Toyota Camry Hybrid

While driving I attempted brake to slow entry into uphill driveway. All lights on driver panel lit up. Brakes did not respond to slow down or stop. With full force I depressed brake pedal. Since drive way was uphill, I coasted to stop just short of garage door before crashing. This was not the first time the brakes totally failed during last couple of months. I drove to dealership for second time to have beaks inspected. The car was also making loud noise whenever brakes applied. The service manager said the brake system was examined by several technicians. Again, they found nothing wrong with brakes and told me the car was safe to drive! despite several recent brake failures, two visits to Toyota dealership, the service manager said the loud noise when braking came from the "brake actuator," which could be replaced for $2,900! quote from service invoice of March 18, 2014, follows: "tech 165630 performed diagnosis on brake noise from inside cab of vehicle. Test drove with customer to verify noise. Found that brake actuator is the cause of internal noise when at a stop while brake is applied. Suggest new brake actuator and brake flush and re-test for noise again. " service manager and technicians said, "it' safe to drive. " I do not believe it is safe to drive. Since I am a visiting hospice nurse, that car is my office. I wonder when the brakes will fail again, and when the incessant loud noise will stop. I took the car to an independent foreign car repair shop. They said, "the actuator is the source of the noise and your braking problem. However, we can't get an actuator to replace Toyota's part because it is a "locked part" in the engine. Only Toyota dealers can obtain the part, and only a Toyota dealer can install the part. " will you help?.