Local folks can probably give you a better answer. However, the Narrow Gauge Railroad Inn (719-376-5441) is definitely within easy walking distance of the C&TS Antonito station. We stayed there last fall between the two days of the Trains Unlimited excursion.
I rate the room I had at the Narrow Gauge Railroad Inn as acceptable, but not luxurious. I'm actually more enthusiastic about their restaurant. In spite of seriously overworked wait staff, we had a good dinner and an even better breakfast, including pancakes that lapped over the edge of a dinner plate - best I've had in a restaurant in many years.
Antonito also has at least one other motel - the Park Motel (719-376-5582 ) is a bit further away. That's all I know about it, except to say that it got the overflow crowd that Trains Unlimited couldn't book at the Narrow Gauge.