1991 Toyota Tercel Replacing head vs. Engine?

Hello,
The top of my radiator cracked while I was driving. I cooled down engine for 30min. Then drove 65mph for 6 miles. I drained oil pan and no antifreeze found. I drained radiator no oil found. I replaced my cracked radiator with a new one. When I poured in the antifreeze a leak started at the manifold gasket. (FYI: Entire exhaust replaced last month, manifold to tailpipe) I emptied the radiator. Pulled the spark plugs to find second plug wet and antifreeze leaking from only second cylinder. I'm going to have head checked but would it just be cheaper to replace the engine? I've already put alot in this vehicle and expect more but I want to do it right the first time. Thanks for your help. I've read alot of other posts that were helpful. Hopefully you'll be able to pin point an answer for me. Thanks again