The only one that could pack you in on horses (unguided or not)for compensation would be the outfitter that has the lease on Montana side, and he would only be able to take you to the Idaho border. I have guided on both sides, Idaho and Mt. We sold out Mt to Tom Henderson about 15 years ago. Call Dave Kozub (406) 538 6516, he should have Toms # for sure. (406) 363 3281, (406) 363 0403. I am not sure those #s are correct, pulled them from phone book. May try (406) 375 0070, or (406) 642 3262 or (406) 285 3541, they may have horses for lease also.I think Tom still has that FS lease for alot of west side Bitterroot to Idaho. Check with MOGA websight, you should be able to find who has that area now for sure.
Dont get in over your heads. Even experienced and fit woodsmen can get into trouble in that country. It is tough to get horses to alot of areas to pack critters out, and 15 to 20 miles is a long way to make several trips with meat on your back. The outfitter I worked with on Idaho side found (2) deceased military men one spring while packing in. They had been missing since the November before, he also had a woman wander form camp that was never found. So most importantly, plan your trip well, good luck and be safe!