Sundays at Six is generously sponsored by: 1st Southwest Bank, Alamosa Convention and Visitors Bureau, Alamosa Local Marketing District, Arby's. First Southwest Community Fund (rural only). 970.375.1100. Alamosa. 1st Southwest Bank (Main Branch). 719.587.4200. San Luis Valley Development Resources. 1st Southwest Bank. Home / Point of Sale / 1st Southwest Bank. Chimera Communications, Inc. 863 1/2 Main Ave. #8 PO Box 4448 Durango, CO 81302. 970.759.6343.