head gasket

[Jacks23]

My 2006 Baja has 143,000 miles. I am up on my maintenance and intend to keep this vehicle as long as I can. Recently, I had to bring my vehicle for a check engine light diagnostic to my local Subaru dealer. It turned out to be oxygen sensor which I replaced. In addition, as part of the diagnostic, I was informed that my head gasket is leaking oil. The recommended repair including timing belt, oil seals, and head gaskets and labor of course would cost $ 2100.00. I got myself a printout of the parts required and cost ( $ 363.00 ) so at the very least if I go to another mechanic I will use Subaru parts. Is this problem an issue with Bajas in general? Could I have prevented it? I live in Asheville, N.C., can anyone recommend a mechanic in my neck of the woods?