This is a fairly common problem with the toyota V6 along with the headgasket.I got one for 175 new at a wrecking yard. You could try ebay I've seen some on there for less then 100 shipped but I dont know about the quality. As for replacing it the job is easy as long as you have basic mechanic skills it should be no problem.Here is a link to a factory service manual if you need help http://personal.utulsa.edu/~nathan-buchanan/93fsm/