Sounds like you are faced with a great opportunity to do it right the first time! Some of us have to work hard at breaking engines and such. You don't have to go big dollar parts to make a lot of power and reliability. I suggest that you start at the begining and find a machine shop that can (and in this order): verify your block and heads are rebuildable; line bore the crank saddles; surface grind the decks on the block THEN bore it out; consider a new crank if it won't clean up at .010/.010. Balance the things that spin and go up and down. Replace the Harmonic balancer if it looks cracked and stuff. If you have California heads, consider getting older 302 heads, or better yet, 351 W heads for the larger valves and combustion chambers. (The valves in these heads are also able to be adjusted) Surface grind the heads, replace the guides (brass liners are great) and replace the exhaust seats. Full cam kits come with new springs, and are not too much. A double roller timing set is a must. A cleanly machined engine will give you years of peace of mind and effecient operation. Done right, you will get enough power for your needs for a long time to come!