Buy new transmission or take a risk with used car?

Hi reddit, so I got into a pickle with my car. I’m a 20 year old female college student, my only way of transportation to and from work and school is through my own vehicle. I bought a 2013 chevy equinox for the majority of my savings (6k) about two years ago, 4 months in the engine destroyed itself through the timing chain. I was advised by adults to pay for a new engine and paid for a new rebuilt engine (Jasper) for 9k including labor (6.3k without). This turned out to be a bad idea because just about one year later, today, my transmission is shot. We were quoted 4,200 (Jasper) for a new one, not including labor. Should I just buy the new transmission or try and sell my engine for hopefully a couple thousand. I’ve got 1.3k in my savings right now after paying for college and will have to take out a loan for any used vehicles. The engine has 12,000 miles, would it be worth to sell? I live in michigan. Any suggestions are greatly appreciated..