why dont you go with a 400 ? is a stronger block they are cheap and you can use everything you already have plus there are off the shelf pistons for it (cheaper)
and ttf member cw25 is running 1.10 ar on his 400 iirc.
The 400 is no stronger than the 383 413 440. They are all pretty much the same blocks other than stroke and the deck height on the 413 and the 440. Even the 426 is close to the same block.
I did see the truck over on ttf and spoke with him a couple of times.
