Do you carry a smart phone?

If yes, then this:

https://f-droid.org/en/packages/ch.blinkenlights.android.van...

will play flac from your phones local storage (you have to transfer the files to the phone of course).

similarly, apps such as pulsar in the android play store support playing audio files (incl flac) from storage

If you want a new device, these are not too expensive and well supported by Rockbox: https://www.rockbox.org/wiki/AIGOErosQK

Or get a used iPod. That's what I did.

another ($250) option is https://www.crowdsupply.com/cool-tech-zone/tangara

> Tangara is a portable music player. It outputs high-quality sound through a 3.5 mm headphone jack or Bluetooth, has great battery life, and includes a processor that’s powerful enough to support any audio format you can throw at it. It’s also 100% open hardware running open-source software, which makes it easy to customize, repair, and upgrade

[delayed]

Warning against Shanling devices. I bought a M0 Pro and it worked fine for about a year and then stone dead. No customer support at all.

Now I'm looking at the Sony Walkman waterproof headband MP3 players. They were released almost 10 years ago, but price, function and quality seem to be good. No FLAC for you though.

iphone5s