There is very little that canbe done cheaply with the 3.0. You are looking at about $1000 for head work, new headbolts(must buy new) new factory gaskets, new knock sensor and KS wire(another must buy), along w/a new timing belt, water pump, and valve adjustment. Labor to tear it down and rebuild it will run you another $1500-2000, this is why so many clean 3.0 rigs are sold so cheaply when they need head work.
If you decide to have it repaired and have a choice, I would go w/either the dealership or certified Toyota repair facility, if niether one of the those are available look for a mechanic that has repaired 3.0's. and knows exactly what must be done to service them correctly. Cutting corners on these engines will just lead to having to redo them again down the road in a few months to a year. If you don't use a dealership, make sure you actually see the old parts like the head bolts and knock sensor/ks wire, if the shop doesn't produce reciepts for the new parts as well as the old parts, refuse to pay until they do. If the shop didn't cut any corners, they wont have an issue producing the reciets or the used parts.
