Help me source ED521 DC Calibrator's transformer

[CrazyTiger]

Hi,

I got a ED521  DC Calibartor with a defective transformer. The unit kept blowing its fuse, and upon checking I found the transformer itself the culprit. Just to confirm I isolated the transformer from the circuit, even with a series light bulb, the transformer produced magic smoke. Now  what can I do?

I can no longer find people who does rewinding for tiny transformer any more in my country. My only other option is look for donor unit or make this as a donor unit. 

[precaud]

I have a 520A parts unit, if that can be of use.