Lets build a new engine.

You can do it and make it live with a four bolt main capable block. It may not a bad idea to keep your eye on Crower's clearance items, they have some pretty good cranks on there on occasion. Many are ground for Chevy rod journals and will give you more options in the rod and piston department. They usually have strokes in the 3-1/8 to 3-5/8 range.