From a SABA 4000 Stereo Console.  This is a Hammond tank type reverb unit.  I have not opened it up, but know that the springs that hold the ends are present stretching it out across the tank, but there are 2 springs on either end that also help center the spring set.  One was loose inside and I've got that taped on the mounting board.  The other may be inside or you will have to add a spring.