This is a Sources Sought notification to identify any ISBEE or IEE vendors that are interested in supporting this project - Appraisal services of nine tracks of land in Washita and Custer, OK. See att... This is a Sources Sought notification to identify any ISBEE or IEE vendors that are interested in supporting this project - Appraisal services of nine tracks of land in Washita and Custer, OK. See attached Sources Sought Notice and SOW for more information.