The old doors we found in Santa Fe are perfect when connected to head rail roller hardware and used to separate rooms. A good source for doors and reclaimed wood objects is:
La Puerta Originals
4523 NM-14 Santa Fe, NM 87508
This company scavenges old wood and makes things such as cabinets, tables and doors out of reclaimed wood. Everything is done by hand and everything is staggeringly expensive. Most items end up looking rather beat-up but some people like that look. Their custom work is great.