I'd say you did okay depending on how the rest of the car is. I see the prices vary on those cars with restored 301 T/As asking 15k to 20k. I'm not a fan of those cars but, I'd say the trade was equal. With looking at the pictures of your Satellite with the faded paint and needing more than my car did I would say 6k tops for the Satellite unless you had stuff done to it.
I had our 68 Coronet 440 for sale recently and I am deciding to keep it for now. I know your pain in trying to sell. I had one guy offer $5500 for it. Now, it's a little better than your car and my car has a new interior, tires, wheels, exhaust, and suspension plus the engine was freshened up. Plus, I have started cloning into an RT.
Anyways, that Satellite would have made a fun driver. If it wasn't too rusty I would have spent a several hundred on the 318 to pep it up. Put a cheap exhaust on and some decent tires and some seals. Maybe do the suspension stuff from PST and call it a day.