Here are parts like we use. You can probibly get them from McMaster Carr or somewhere else, we normally just order from here though.
Valve: http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=13135635&PMT4NO=93982878
Copper float: http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=7211479&PMT4NO=0...