Any option to get "more" power out of an engine costs $$$. When it comes to engine swaps, and you are not giving it to someone who has done it before, be prepared with $$$$ and time for lots of things you may not be aware of. Google searches will bring up most of the common things to know.
To do it properly, doing spanner works myself, I costed/estimate a $10k plus exercise when I looked into it (engine, all engine service items to do when engines out, gearbox, driveshafts, engine management, accessories, dyno tuning).