I think the list you are recalling is the list of Surviving Artillery started by the late Wayne Stark, but now kept by someone who didn't learn the concept of sharing in kindergarten -- hence he keeps it as his personal property and answers inquiries infrequently when he feels like it (which is to say never when I have asked a well intentioned question) That is why he doesn't know about the current location of my tubes (nor the couple dozen my more serious cannon collector friends' have). Most of them are on the list (but not all -- eat your heart out list horder) but the location is wrong. Too bad the list is getting worse under his stewardship but its 100% his fault.
I have an old printed copy of it (which is to say the only means of searching it is to do so painstakingly by emike power). Most of the tubes that are in public places are still at those locations like presumably these 30pdrs. The list has the type, size and serial #s if available by present location. It doesn't tell the wartime history of the guns. I think you know where these 30pdr Parrott rifles are now, and so you will want to do a different type of sleuthing to find where they were in the Civil War.
My understanding is the US Navy kept good records of the cannons aboard its ships every 6 months. Perhaps the ORs (which are searchable) might have reference to these tubes if they weren't on a ship ever.
Good luck,
Mike
PS: Did you ask the caretaker at the location? Sometimes they have info like this.