Apple Refused to Sell Me a New Battery- Other Options?

Brought my 13 Mini into Apple to get a new battery installed, it's not under warranty and the phone has been through a lot but everything else works fine. I just want to purchase and have installed a brand new battery so I get a few more years of life out of it.

They refused to install a new battery as the tag inside showed exposure to moisture.

Does anyone have any suggestions for a third party for a new battery? I understand this will most likely mean me installing it myself.

This will actually burn me off of ever using Apple ever again if this is a hinderance in me continueing to hse my 13 Mini. The phone is fantastic and still works exceptionally, other than the 74% battery, which is understandable after years of usage.

I am completely infuriated right now. If you had a car with "water damage" you could still get a new battery installed. This is all a scam to force you to update your phone to the newest model.