Turns out live ship tracking APIs are expensive so I manually just copied the json from https://www.marinetraffic.com/en/ais/home/centerx:57.4/cente... I'll probably have an ai agent do the same thing on some cron interval, if this gets any fanfare.
To actually know if the port is open without live ship tracking I found https://portwatch.imf.org/pages/cb5856222a5b4105adc6ee7e880a... which was perfect, except it has 4 day lag!
I also thought of adding news feed parsing or prediction market data to get a more definitive answer on if it's open right when you load it, but I spent a few hours and am gonna move on for now.