There’s a lot of gamerips on https://downloads.khinsider.com/

If you want quality for classic Nintendo, you’re probably better off with midi files, which are like sheet music for a synthesizer your computer can play. This way it’s original full quality sound without any recording/large files.

VLC/Windows Media Player can play them if you download a soundfont like general montage (gm.sf2) or in Nintendo’s case, there are a couple Nintendo soundfonts you can search for like this one for the NES: https://musical-artifacts.com/artifacts/610

You can search up a few good modi archives like https://www.vgmusic.com/music/console/nintendo/nes/