More pictures of other cylinders/pistons/ and bearings would be nice.
That cylinder, and rod bearing looks to me that the rod is bent, or the rod journal on the crank, is ground crooked. The rough scoring on the crankshaft, and bearing is from debree, or some lack of oil pressure at some point. It does not look blackened from lack of oil over a long period of time.
Number one cylinder is the last to get oil pressure in a SBC, or BBC for that matter.
From what I can see of the top of the piston, it does not look like a ring problem. If it was, the quench area would be washed clean of carbon. I would look more into a valve guide, valve seal, or intake gasket leak.