what size BB stroker is best for race only with stock block?

I'm looking at 2 different heads. Either a set of victor max wedge heads or a set of Indy's. Would have both cnc ported. My own idea was to run the 470 engine. I've heard a lot of good info on them. I have the max performance big block book. I have no problem running other brand rods. Who sells the good stroker kits? Or would I be better off buying everything separate and get what I want? I'm probably going to send it to MRE to have it all balanced and probably send the block there too. I've heard nothing but good news from them. I use a local shop around here but don't want them to do this engine. They do good work on stock to mild but I want the best I can get. I've learned in the past not to go cheap on the machine shop.