here, I attached a shapefile (climstn.rar) of rainfall stations, collected from Bangladesh Agricultural Research Council ( http://www.barc.gov.bd/).
For river hydrological gauging stations you could visit Flood Forecasting & Warning Centre's webpage (http://ffwc.gov.bd/) or contact Bangladesh Water Development Board [BWDB] ( http://www.hydrology.bwdb.gov.bd/ )