I bet its an 83 or early 84 with the casting defect. The crank is good if it was done right, the block is junk if it cracked...it can be repaired, but these blocks are tough to weld and fix right. The pistons are probably good if they haven't been used since the rebuild. Its up to you as to if you'd want to use them in your rig. New rings you would definitely want with all that rust in the cylinders, new bearings are good insurance. A new oil pump would be a good idea unless it was replaced with the rebuild. For $100 take it! Its worth that in scrap metal alone, plus a good set of IDI heads is worth good money.