If you can't swap the input pins 2 and 3, then the next best thing is to invert the output with a transistor (rather than a NOT gate).
Just add an NPN; existing D output to NPN base, emitter to ground, collector is your new output. Note that his arrangement only allows you to "sink" current from the new output. If you need to "source" current, then use a PNP instead; existing D output to PNP base (through a series 1K resistor), emitter to Vcc, collector is your new output.
You could implement either via lifiting the pin(s) and "air wiring" a transistor[+resistor]. I doubt you'll find a '393 equivalent with swapped inputs or inverted output.
See below and
here for the simulator.
Note: quirk of the sink driver has the on-board LED always on.