If it's not number matching, build it the way you want to. If you are looking for speed, take a 440 block, stroke it, and put aluminum heads on it for a little weight saving. If you want handling, build a small block stroker with aluminum heads and cut the front end down some.
Me, I went with the Hotchkis suspension for handling and a bb stroker for speed...
Once it is not numbers matching, you are not going to hurt the price by modding it, but you can make the price better by doing it right.