What I suggest is don't bore the block any more than it needs to be to maintain it's durability, and then whatever displacement that produces with a 4" stroke is what you get.

Here's a carbed example using either Patriot or RHS heads, the Comp Cams 35-243-4 flat tappet, a larger single plane intake and carb, and larger tube headers bolted to a 0.030" over 351 block with a 4" stroker crank installed. The RHS heads can be had for about $1000 fully assembled and flat tappet cam and lifter kits are only about $200. If you packaged this with a cast stroker kit and didn't spend a bundle on the intake and carb the motor could be done for around $3000 or so which is pretty incredible.