If you'd like to do something similar, but don't want to DIY it, check out Yoto Player [1]. This is a small music speaker and they sell a bunch of NFC cards to "play" them. You can also buy blank cards and use their app to add whatever you want to them (music, audiobooks, even audio recordings). It's really well made.
There are a bunch of other companies with similar products. Some use miniatures instead of NFC cards. If you search the web for NFC music player, there are a few FOSS apps on github so you can focus on the hardware part and use their software on a raspberry pi.
This is also great for elders.
P.S.: if you fancy a cool project, I'd love to see someone reverse engineering Yoto so it gets the audio from a local server instead. This way we can use their great hardware, but can use any NFC cards.