"
non-resident can buy a bull tag for 2015.". This disclaimer closes a lot of doors. That means that you either go private land with PLO tag and not go very far back in or an OTC hunt. Most really good honest outfitters are already booked for 2015 with repeat clients.
Private land is the big option, but that almost doubles the price. Also, even outfitters on private land, to do pack in hunts, usually have to go into wilderness areas. However, at times their access is the only easy way to get into there. If you have the bucks , there would be no problem. OTC means mostly public lands where success ratio goes down dramatically.
In Colorado, it is hard to go further than 6-7 miles before you start meeting hunters coming in from the other side. Montana & Wyoming have bigger tracts of public land.
You might look into these guys. I think they go back in 25 miles or so.
http://www.royaltine.com