Oh dear God! 318 stroker

Part of what we live with is working with the parts that are available and affordable, unless you have unlimited resources. If you are going to bother stroking it, 390 is where it's at. You can get a kit that is already all scienced out or you could probably send your block to Blueprint and they can return it as a 390 complete with a warranty, rather than spending a fortune on machining something that is otherwise unavailable.

You will find lots of experienced folks here willing to help you out and sell you parts that you need - Welcome Aboard!!!