engine swap? rebuild? what should i do?

right now i have a stock 90 ls setup with almost 160 miles on it. i want to make my car faster, but i dont have alot of cash. ls/vtec conversion looks too complicated, and i want to keep my car reliable. should i rebuild my current engine and put on a turbo or something or would i be better off to get a jdm b16a? where can i find a good place to buy an engine?