You'll spend alot of money to get a pretty unimpressive gain with a non boosted 3K or 4K, you will have alright smooth power but in no way a rocket ship.
If you just want it going decent for a stock motor, give the head a reco. rebuild the carbie and sort out the timing that will at least get it going ok.
sort out a budget and that will give peoples comments a much more focused response. can spend 2 grand very quick on these engines