... just an idea
I have been looking at the following schematic ... with reference to your request:
**broken link removed**
I am not completely confident about it, but there may be a way to modify this circuit to conform to your specifications.
You would remove the bridge rectifier component, as well as D11, and connect the 730 to 380 DC voltage across the resistor divider chain ...R2-R3-R5-R6.
If I understand correctly, the purpose of the diode bridge is to supply the zener diode, in order to get +9 volts to supply the chip. You might construct a separate voltage divider, with reference to ground, to supply a zener diode, in order to accomplish this.
.... probably need to draw up a new schematic, just to make sure that everything is clear.