I have a 2010 Toyota Prius with a blown head gasket. The original engine died at 225k and I put a second engine in, my mechanic now says that unfortunately the head gasket is leaking at 260k. To make matters worse the second engine warranty has expired. **Currently there is no coolant in oil and no smoke from the exhaust. There is a small amount of white smoke coming from the engine, plus that knocking sound when the car is first started.** My 2010 Prius 4 with solar package is in excellent condition inside and out (garage kept). Looking for mechanic recommendations in the northern Pennsylvania area, I want to get a second opinion on the engine. I'm really looking for a Prius specialist if possible. Any recommendations? If I have to let this car go I will, but I want to see if an economical repair is possible. Thanks in advance for any comments.