i get most of my "foam" insulations recycled from roofing and demo contractors. this I believe mitigates the embodied energy
search craigslist/kijiji for da bargains.
polyiso is not blown with cfcs.
I have never seen polyiso that didn't have strengtheners. so check, but it shouldn't be hard to find. I've used Dow, JM, IKO, foil and glass faced. all have had reinforcement.