I bought one of the $25 special 12mm 12-point sockets, and it worked great, but I did recently see a set at Pep Boys with a 12mm in it. my bolts were so tight we had to pull as hard as we could with an 18 inch breaker bar, and hammer down on the socket to break the bolt loose. When installing, it's the scariest thing I ever did to a car; you torque to 50 lb-ft, then add 90 degrees, then ANOTHER 90 degrees. That last quarter turn will feel like you will certainly break the bolt off.
That being said, maybe the Chinese Pep Boys special will hold up, maybe not. Also, I think I would just replace the head bolts on principle, not too expensive, and when you are cranking that last qtr turn, you will appreciate having them. The thought of breaking a bolt is not a pleasant one.
Mine leaked water at exactly the same place, must be common.
Before, it would use a quart of oil on the the highway in about 3-400 miles. I had the head reworked with valve job, seals and guide bushings while it was off, and the oil consumption dropped to negligible.
Worst part of the whole job was getting the chaine tensioner back in - gotta push hard and turn with something at the same time. I made a tool from a bolt head and a nust that worked okay, just be inventive and patient.