Well, perfect is only available with a few natures (modest, timid, calm off the top of my head) but you can get a "perfect" azelf in the sense that you don't care about some of the stats.
And as far as I know you can get any pokemon with a normal date as long as you can hit high delays and have a 3rd gen cart, if not then you may have to change the year.
And as far as I know you can get any pokemon with a normal date as long as you can hit high delays and have a 3rd gen cart, if not then you may have to change the year.