Rebuild or replace for a 1979 ford bronco?

i have a 1979 Ford Bronco, im a big chevy man, but i love all clic cars and trucks, i would like to rebuild the original block but there is alot i would have to do to get the horse power i want out of it, so first question what would yall recommend on rebuild parts/performance parts, then if i was to replace what is a good website or company to go to thats not to expensive to get a engine and transmission from, mind you this truck will be a off road truck and i have a lift and tires on it as is so please help me out the best yall can.