if money is not an issue do the 3s swap, if money is get a turbo and manfold from a mr2. (3S-gte) and it will bolt right up to your 5s,
you will need to make a downpipe, oil and water lines to make it all work, and a few fuel system tricks to get it to handle boost.
nothing about the turbo conversion is very hard. can be completed ina day or so.