A potter friend from the Ceramic Arts Network Forum, Mark Cortright from California, said that he uses "end rolls" from a local newspaper printer. I decided to look for a similar arrangement near me. There aren't many newspaper printing plants left, but I found one in Frederick, Maryland. Turns out they sell their end rolls for between $1 and $4 each, depending on the size. Jackpot! I drove out there yesterday and drove away with this. I think this will last about a year, and I only spent $47.
To any other potters within driving distance of Frederick, Maryland, you can buy end rolls at:
Frederick News Post (FNP) Printing and Publishing
351 Ballenger Center Drive
Frederick, MD 21703
https://fnpprintingandpublishing.com/
They typically have some available everyday. Though not TODAY, because I just cleaned them out. You can contact them in advance to make sure they have some. Or, you can walk in the main entrance and ask at the front desk.