engine replacement

Hi all, I'm doing some research on replacing the 2.4L in my TJ. I'm at the end of nearly a year and a half saga of my jeep cycling between drivable and not drivable. At first I was having overheating issues, then the engine started blowing oil out of who knows where that the mechanic couldn't...

My engine seized due to lack of oil - although I did have an oil change less than 2 months ago. I am wondering your opinions and advice on selling the Jeep as is, or replacing the engine with a used engine instead. The quote I received from the auto shop for a new engine replacement is $4700...