Most Digital Audio Players now are hi-fi oriented. The current gen baseline sony walkman starts around 350-400 USD. Is part of the reasoning behind this that you like wired headphones? Have you considered getting a Xperia phone and reduce the amount of devices you need? Maybe check out the Shanling M0 Pro. Its the cheapest good quality dedicated player I know of.

​

Edit: one last thing, anything with a battery built it inherently has a limited lifespan. expect 2 to 5 years max