I don't understand, your car is completely paid off and you can't find a subaru dealership that is willing to take your impreza in trade for a wrx???

Also, i think a wrx-to-sti swap would be, not only easier, but also more rewarding in the end. if you wanted to do an sti swap, then I'd be chearing you on, but honestly the money it would cost you to swap your car to a wrx would be a waste, because you wouldn't be satisfied in the end.... it would just be the begining of a new project: upgrading your wrx to an sti