C152 and Pa 28 really are apples and oranges. You do circuits in a C152 and you can go touring in a PA28. What do you want to do?
As for engine overhaul, my pals just spent $40K on an overhaul for their time ex C172S engine. Prop OK. The LAME wanted 4 days work to remove and replace the engine.
As said before, if it flies, floats of fcuks never buy it, rent it.