2001 Other Saturn Models Engine problem escalated to its fin

Two weeks ago my Saturn SL2 began developing a knocking in the engine when the car warms up. Mechanic I brought it to suggested Lucas oil treatment for 500 miles to see if the honey thick medicine would decrease the problem. I changed the oil and filter religously every 3000 miles since I bought it new in 2001. Anyway, the knocking, valve tap would disappear and reappear at will during my drive to and from work, sometimes during acceleration other times upon letting up on the accelerator. Then last Friday I drove a little longer, abot two hours and the noise got louder and louder. Got home chaneged oil and filter, pulled a plug out and the bottom was dripping with oil. Blown Cam?
Due to age? Options? Suggestions? Thanks in advance.