Replace Engine or Used Car

I currently have a 2006 Toyota Rav4 Sport with 278,000 miles with a busted
engine (it is predicted to last 500,000 miles). I have multiple options, but here
are the main two. I can either replace the engine for $5,000 or I can get a used
2006 Toyota Rav4 for $5,000 with 150,000 miles. My question is whether I
should replace the engine or buy the new car? Should I get a new engine for a
car with almost 300,000 miles (and could potentially last 200,000 more miles)
or should I buy a used car with 150,000 miles with a 13 year old engine? New
engine with more miles or old engine with less miles?