Subaru impreza ej25 and drivetrain swap or engne build on a fs-de 2.0?

I really don't know what to do with my engine i would like to create my mazda protege mp3 into one of the fastest possible but i have money i have to worry about on the other hand i'm a big fan of the subaru impreza's espescilly the ej25 engine and the symmetrical awd. I was wondering if it would be easier and better to swap a wrecked impreza with a usable engine, drivetrain, and ecu into my protege mp3. i really love this thing but right now my engine is blown and i can't drive it. Can you tell me which one would be better and easier? Still, remember i have money I need to consider as well.