Available countries & periods

For dedicated per-IP products (IPv4, IPv6, ISP), the live list of countries you can order and the rental periods available, so you can build a picker without hardcoding anything. Countries come back as { name, alpha3 } and are kept current for you: the list is refreshed from stock and a country that has run out is removed automatically, so what this returns is always orderable. Feed an alpha3 straight into the country of price and orders, and a days into period_days. Gateway products (delivery is lines: residential, mobile, ISP rotating, IPv4 and IPv6 per GB) have no per-country configurator and return 400 no_options: they target by country at generation time instead (see generate).