It turns out there are no moose guides in this area and that most of the most reside along the river between Rexburg and Saint Anthony
I worked with the local biologist who kept me updated as I just had transferred to BSU. She was awesome. You may want to see if any landowners have their land open for moose hunters.
Also, look for any parks. I shot mine at Beaver Dick Park (I know terrible name). I fished that area a lot and always saw moose. Maybe you can find similar areas along the Snake.
Start there and you might have some luck.