Occasionally I am asked if I make my own warka. No, I don't. Warka making is a specialized skill that takes considerable practice. An old North African recipe for pastilla (beestiya) begins, "First you hire a warka maker to come to your home". A recipe for warka can turn into a recipe for tears and frustration. It takes lots of patience.
The warka maker's job is endangered these days by the many commercially made versions that are very good to excellent. While this is unfortunate for warka makers, it does make the pastry leaves more accessible and affordable for a more typical home cook. They are available to the trade in the States and you will see them on menus for items such as beestiya and croustillants. In France manufacturers label warka leaves feuilles de brick. This is an Algerian influence, warka is also called brik in Algeria as well as dioul and malsouka.