Hi, first post here and it's for requiring your help

I stupidly blew a regulator on my ZD-915 power supply by inverting wires when connecting the output to a DC-DC converter. I had replaced the cheesy "voltage dropping" device installed by the manufacturerwith a nice adjustable converter and testing went well, now motor and fan are receiving the voltage they are designed for,i.e. 12V.
Unfortunately, when rewiring the thing I inadvertdly inverted positive and negative wires on the DC-DC converter's input. Of course when I powered it, regulator T1 was instantly blasted, so badly that I can't even read what was written on it (see photo).
Here's my question : what part number shall I order to repair the PS ?
Thanks !