My proposal: Create a project.

Project name: Getting specific documents
1. check on which days the place is open for your visit = next action
2. ask your boss to get a day off (@work)
3. put that specific day into your calendar, thereby you'll be reminded right on when you'll have to go.

I know, for step three David Allen usually suggests to write on a context list. But in this case I see it as a calendared action which can only be made on a specific date.