So it looks like the transformer is rooted!

Hi Chris,

Hmmmm ... transformers are pretty simply devices not that prone to failure.  I'm not familiar with Sterms, but you sound despersate, so a few ideas;
 -  History of the machine - is it wired for the correct voltage?  If it's configured for 110V input then the output voltages will be approx twice what they should
 -  Remove all connections and just use the meter to measure transformer output voltage - with nothing connectied it should be a bit above the nominal voltage. What is it?
 - maybe post a fragment  of the schematic of the area of interest and you might draw a few comments and ideas
 - test rectifier board into other machine

Good luck.