An Aussie meat pie usually has twin kinds of pastry. A kind of short crust which uses lard instead of butter which makes it dense and hard so you can grip it in one hand without bending it. The upper crust is usually a puff pastry, but my favorite pie topping is mashed potato which goes all hard and crispy.
And yes, it's normally served with tomato sauce.
Pasties, traditionally, are last nights baked dinner out inside puff pastry. Meat, potato, peas, carrots all inside a pastry shell folded over. Sweet ones I call a turnover.
We have pot pies quite a bit at home because they're easy, just filling and pastry on top. I make chicken and leek, DH makes beef and burgundy. But the best pies we have are the shepherds pies we make with leftover roast lamb. We get a leg of lamb that's a bit too big for us, roast it, eat what we can and use the rest the next day for pies. Magnificent.
I can make pastry, but DH says I make it too thick. I usually use butter but I also have a recipe for olive oil pastry that's not bad. Pastry does work best with butter though, the olive oil lacks crumb lines and elasticity.