1964-1969 Rambler American. The base-model 220s and 330s. You can still get these cheap, especially 4-doors and wagons.
My dad had a '65 220 wagon. It had a 195.6 OHV I-6 and a 3-speed manual trans with OD. He took it in trade for a job. That's how my sister and I got to school when we were little. We also took road trips in it. He drove that thing well until I was an adult, it still ran, and he wound up trading it for a '67 F100, which he still has.
I loved that car, and if I ever see one for sale in my area, I would buy it.
My dad said he would get 35 MPG with it. First car I ever drove. My sister and I could drive that car before we were 13, and he taught me how to work on it. To this day, it's the easiest car I ever worked on.