How to store my roll up banners.

I recently purchased several roll up banners for a seasonal decorating project I did at our local community center. Somehow the boxes the banners came in was misplaced and thrown out and now I’m not sure where to find or buy the right storage box for them, since I’m sure we will be using them in the years to come. They roll up so beautifully however I am nervous they will get crushed, bent or ripped if they are not stored properly. They are rather large pieces so the box would need to be at least 42″ long. If you have any suggestions, please let me know.