All of the current M9's that are produced for civilians are Model 92's stamped M9. The markings are not identical to real military M9's.
Beretta made a run of government approved M9's with all of the correct markings many years ago but these have mostly been snatched up by collectors and bring $800+ if you can find one for sale. I have two of them and this is what they look like:
The dust covers are straight whereas the current "M9" being sold on the civilian market are tapered. The markings on the above M9's include the proof mark (PM on the slide) and the correct assembly numbers including the hammer. The guns above also have a steel guide rod whereas the current civilian M9's are plastic.
But, for all practical purposes a civilian M9 is a great gun and you would enjoy owning it. You could shoot it and not feel guilty for putting wear and tear on a collectors item. They run the same, mostly look the same and most people couldn't tell them from the real deal anyway. Plus the price is around $500 which is a good price.