This looks like the gridded screen with a center micro-prism. It's not an acute matte. My reference material isn't handy, I don't remember the "official" name.
Also, as I recall, the acute mattes have a notch along one side.

It is a nice screen though, my 2nd favorite, though I've never used an acute matte. It's not as bright as the A-M, but it may work well for you. However, if the camera was priced according to its having an acute matte, the seller may owe you some money.