What can I use for non-photo ID to get a PO Box?

I'm a minor and yes, it's legal for me to get a PO box in the States. I want to get a PO box (personal & appropriate reasons) but I need a non-photo ID. I have a photo-ID already.

On the USPS website, it says that I can use:
"Current lease, mortgage, or deed of trust
-Voter or vehicle registration card
-Home or vehicle insurance policy
Note: Social Security cards, credit cards, and birth certificates are
not acceptable forms of ID."

Since I'm under 18, I don't have any of those things.

However, I do have various pieces of mail from my town and high school that I go to that have my name and home address on it. Also, I have lots of mail from shops (like American Eagle Outfitters) that have my name and address on it…

Plus, I have a library card too, but it only has my signature on the back.

Basically I'm not sure how strict USPS is about the requirements of getting a PO box, but I want to stay on the legal side and not forge anything.

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