Depends on where you live.
I have a jeep with a 360 in it and it gets hot as hell.
I put a new 4-core (DON'T ACCEPT ANYTHING LESS THAN 4 CORE IF YOU GO THE TRADITIONAL RADIATOR ROUTE WITH A V8) and it barely does the job in AZ. A new traditional rad is 200 bones. Again, 4-core will help a V8 but not as good as an aluminum rad.
Take the advice here and spend the 400 bucks on the aluminum---your temp needle won't budge much past "C."
Winter's coming, I realize. And all this jibberish will be moot...if you only have 200 get a new 4 core. If you posted this in March, get an alum. It all comes down to summer for a V8...