Methinks.......
that unit is a common industrial unit...categorized as a control transformer... at a power dissipation rating of 100VA , therefore not to large of an open frame case profile.
Its primary is wanting to receive 347 VAC and put out 24VAC.
To confirm, use an ohmmeter to differentiate the primary and sec windings and then zero in on the primary winding and connect its wires to a VARIAC so that you could then slowly bring up to a 120VAC input and confirm ~ 8 VAC emanating from the secondary of the transformer.
If so, you are then in the market for a 347 VAC supply source ....hi hi .
73's de Edd