The "notched" collar that we see here has always been referred to as a "Roman Collar" hereabouts. The collar where a white band goes all the way around the top of the shirt has been referred to as a "Parson's Collar".

You can't go wrong with basic black. Let's not forget that the adoption of the religious habit is meant to signify, if not a rejection of worldliness, then a de-emphasis of it. Once upon a time anything but black was only allowed for missionaries in tropical places where a black habit would have turned them into mobile solar ovens.

There are a couple of variations on the shape of the collar in some of the Roman Catholic religious orders. The Christian Brothers, for example, wear a collar with a sort of a split white dickey depending from the notch. One could always spot different orders by the collar variations. Nowadays, I think that they try to keep it simple.

Best

AA