Given the violence and horrendous nature of that period, you'd be hard pressed to find any venue to show such a scene where it wouldn't be found offensive.
Yeah, I know, history, not to be repeated, warnings, blah, blah, woof, woof. However, this was well documented and illustrated in "The Rape of Nanking" by Chang and Kirby, and a model, unless done by an extrememly talented artist, would trivialize it.