Hi. Anoraks, in general, aren't common. (try looking for a sewing pattern to make one. snicker.) Not all armies used or use 'em either. Nor does every troopie get one. And you can get huge arguments as to exactly what each is too.
A waterproof jacket, typically with a hood, of a kind originally used in polar regions is called a parka in most places.
Webster says an anorak is a hooded, pull over, jacket that covers the hips. A smock is a light loose garment worn especially for protection of clothing while working. (I'd bet that saying that near a Para would start a fight.) Difference is the anorak is a pull over wind breaker(have one of those I bought eons ago). While a smock is really a light jacket that opens.
Google for 'anorak' instead of wasting time with Pinterest. Best you have a budget in mind too. $100USD isn't unusual.