360 budget build questions.

Here's the rub as far as i see it - the factory pistons are pressed on. When you press them off chances are very good they will deform. If it was me I'd simply look for another 360 running for under $500, and then add your bolt ons to it. Sometimes we do things to make the effort, and the reward is not really that much. Reusing stock pistons, and assuming the guy that's taking them off won't deform one by accident may cost a lot more, and if he does get them off, you're still stuck mounting the new rods and beign left with exactly what you started with. Another thought is a runnign Magnum engine, in which case you'd need an intake and a flex plate to drop it in. They're probably a bit more common and cheaper than an LA 360.
Up to you.