Where can I buy a new OEM battery

@lightwave62505 It's really hard to find good quality batteries for older products once the manufacturer stops selling them. Anything that claims to be original is usually fake, apart from sites like iFixit where they may have a relationship with the manufacturer to sell original parts. You almost never see actual genuine new batteries outside of iFixit.

I would rather take a chance with a bigger Chinese 3rd party battery brand like Nohon than a "genuine" battery. But even then, expect the battery to last maybe a year or two at most. Aftermarket batteries are just often poor quality.