I can get it locally, they even had a herd at Founder's Ranch (Cowboy Shooting Championship Range) about 6 miles down the road from me that broke out and wandered the hills for a few months.(you do not round up buffalo)Here's part of their property, that's what it looks like in my neck of the woods. I'm pretty much a fixture at their sporting clays range, but I also shoot Cowboy long range (think Quigley Down Under).
Sometimes Costco has ground bison and it's pretty good. The butter keeps it from drying out, it's very lean (not as much as elk though). Not sure if you can find actual NM green chile, but I think some is exported in cans or pouches. Here it's a fall tradition to get a sack or bushel roasted. 