Head gasket cracked

I was informed today that I have a cracked head gasket and now I need to make a decision to either get it replaced or have a whole new engine built I have an '04 4Runner with 278 k I've already invested at least 15k into it since I've owned it I kind of have sentimental feelings for it I really don't want to get rid of it and I definitely can't afford a new vehicle.

 

Unless the engine overheated, I would just get the head gasket replaced.

 

I agree with trlhiker that I'd do the head gaskets providing the engine didn't overheat and doesn't have any other known problems. But, if you were to decide to replace the engine with a used one, be sure to get one from an 06-09. They don't have the head gasket issues.
My 05 blew the head gasket at about the same mileage as yours and I did head gaskets. Also did the timing chains and all guides, gears etc. and a buttload of other stuff like belts, hoses, tensioner pulleys, water pump and probably more that I can't remember now. I did my own work so it wasn't so bad for me but I still probably ended up with about $1500 in parts and machine work.