As Steve said, have you the 4EFTE engine transplant in your Yaris dude? Unless your handy at building engine mate? then i would go with one of the site traders, PP, TMD or TD, all have built up forged engines, and you will get some sort of warrenty if you go with a trader i think? Your looking at around 2K, obviously depending on spec you want. You wont save much that much money i dont think if you buy all the parts seperate, and get the machine work done, and then assembled. TD12 is what you mean i think? I would go for something a little bigger on a forged engine if it were me.