Getting a 318 running?
The original freeze plugs could have been replaced due to rust....
Measure the bores to find out if it was rebuilt or not...
I recommend going with a "refresh". Mancini racing sells "refresh" kits with main and rod bearings, rings, and a teardown gasket kit for reasonable prices. Then make sure to plastic gauge the bearings to make sure that everything is good before the engine is installed in the car....