boxes for storing prints

Hi,
Recently I thought about buying some good carton boxes (neutral pH) for storing my prints, however I've noticed that some people use old boxes from printing paper. Does anyone know if they are neutral pH also? If they were made for storing paper they shouldn't be harmful for silver prints, should they? Or maybe they are made of ordinary acid cellulose?
Thanks in advance

I highly recommend Century Archival products...they are great...they make boxes and sleeves. Original
Kodak/AGFA and Ilford boxes are fine.

Thanks a lot, that maybe a good option. On the other hand, do you have any knowledge about boxes that are used for packaging printing paper, are they modified for neutral pH or normal (acid) as any box?

I have been using empty photo paper boxes for decades without any problems. The archival boxes are good but they are very over-priced.