Generating 5V power from 3.3V powered PIC

I would say that you could drive the LCD from 3.3V.

I suggest you add a resistor of about 330R in series with any I/O that can be an output on the LCD. I think that just means the data lines.

The resistors would mean that the full 5V would only give about 5 ma so the clamping diodes on the PIC wouldn't be damaged.

You might just rely on the LCD not having any outputs if the R/W line is left on Write.

Yes, I will tie R/W line to Write only, so I will need 6 lines: 4 data and 2 control
I am not sure if I use 6 resistors or HCT541 - probably about same cost and PCB space