Supercharged or Stroked 360

400 HP is nothing for a NA stroker...or even stock stroked 360, for that matter. If you want a budget stroker, and you plan on keeping it under 500HP, use the stock rods, get a cast stroker crank (about $300), a set of pistons, good valve job and bowl blend. There are several off the shelf cams that will support it, topped with a RPM Airgap and 750. That will easily get you over 400HP/TQ. If you sell the SC, you might be able to fund the whole build with it.