www.bearbasinpacktrips.com
If you click on the 'Our Trips' link, my daughter and I did the Cowboy Weekend (of course it was the Cowgirl Weekend).
They tend to have small groups on the weekend trips; we had only one other person on the Cowboy Weekend. There were tons of people on the day trail-rides, but we got our own private trail-ride on Sunday. It was fantastic. They customize the trip as much as you want.
The longer pack trips in the Sangre de Cristo Mountains have a limit of eight clients (twenty-five heartbeats, apparently, by law - including all animals and humans).
The food was okay, not gourmet, but good and plentiful. It's byob; they did provide beer at dinner. We slept in tents on low platforms with a foam cushion for our sleeping bags.
The scenery was flat-out breathtaking. The air was the best. Stars - what can I say? Just go.