The port of entry depends on shipping. If the seller ships via ocean, then the port is probably the nearest city to you on the ocean. If it is coming air freight, the nearest international airport. Cheapest shipping is in shipbound container. I imported one off pots from Horst Heinzelreiter back in the day. He shipped two day air freight via Lufthansa. Pots were held at Lufthansa's shipping facility at Dulles Airport which is about 20 miles from me. I had to schedule time from work to go pick them up after they cleared customs. I then had to settle with Lufthansa on extra duties and shipping costs.
https://www.cbp.gov/contact/ports/OR
FWIW, I have been avoiding Chinese containers for a few years now. There are better, more easily obtained and mostly cheaper Japanese pots coming into the U.S. by the thousands. I've had high end Chinese pots for years. My big live oak has been in one for going on two decades now. I have found the quality can be a crap shoot. Some are good, some are sold as good but are crap. I've never had that issue with Japanese-made pots...just sayin...