You are dreaming if you think you will find a rebuilt 360 for $1500. I don't think I've ever seen a complete and completely rebuilt one for less than $3,000. That company you are talking about could NOT possibly be turning out anything other than junk for that price. You can easily get several thousand tied up in just a short block with parts, labor and machine work. Machine work alone (cleaning, turn crank, bore, hone etc.) will likely be over a thousand dollars at a reputable shop. And what if the block needs to be decked or line honed?
Who told you that. Let's say you pay $250 for the engine. In order to be "all in around $1100", you would have to find a shop to do a rebuild for $850. That simply is not possible. Listen, I'm really not busting your chops. You just need to take a deep breath and accept reality. For your budget, you are stuck with a decent running used engine. If you have the mechanical abilities (and if the engine is basically sound) you could probably get away with a freshen up (rings, bearings and gaskets) for not much. Good luck.