i have been through this with one of my client's cars.if you find a used one they are expensive.it also seems that they will all go out after about 13-15yrs.so if you buy a used one no way of even guessing how long will last.i am afraid you have no option but to buy a new one.they are not much more than they were 6 yrs ago.the reason they cannot be rebuilt is because they were filled with epoxy to make them last. david poole european performance dallas tx.