I saw those pins but I was not sure if they were removable. Curt makes a hitch like that. I never thought about not having to grease it or and having greasy trunion bars laying around.
The head is greased with a fitting and the grease stays mostly inside. Curt is my go-to place for most other things trailer hitch related, especially ball mount shanks. That is a Curt shank on my Blue Ox WDH and its price was ~50% less than any other I could find and is high quality.