Uhh, basically everyone here who runs MAME on a "real" arcade monitor does the same thing...
There's nothing special about that Amstrad monitor, just another CGA type monitor that were very common in the 80's.
I use a Philips (some will know it as the Commodore 1084 monitor better) as a test monitor. I even got an extra that will either go in my cocktail or my Missile Command cabaret.
The only thing you need to hook up a (windows) PC is either a software tool (Like Minwah says, Soft15kHz) or use a hardware solution like the ArcadeVGA card from Ultimarc.