The bigger strokes require an aftermarket oil pan. If you've got one, for the 4.25 you have to mod it. If not, then you have to buy one, which will add another couple hundred to the price most likely.
If the block needs reboring, stick to .030 over. If the walls aren't worn enough to need it, see about standard bore.
The block must be clearance for the crank, ground a bit at the bottom.
If you aren't doing 4.15 or 4.25, aren't going to go over 6,500, aren't going to have over 11 psi, aren't going to run over a 150 shot, the cast crank should be fine. Rods and piston are a better idea to spend on.