What do I need to add a standard PC monitor
You will need at least a scandoubler, and preferably a flickerfixer so you can display interlaced screenmodes without any hassle.
actually you will need at least a vga adapter. you can do without a scandoubler/flickerfixer if you can fin a monitor that will sync at 15khz nec3d is good but old there are others including commodore ones.
that results in a pretty pitifull image though all scanliney and such thats why a sd/ff is highly recommended. or an a3000 :-D or video card