On a budget? Don't buy music, stream it. Tidal provides access to nearly all CD quality music for $20/month.
Look to iFi for good really small DAC's etc. (the Nano iDSD is $200, well respected, tiny, and has volume control/RCA output/headphone jack). Just plug into your computer.
And consider powered (or better yet active) monitors for bang for the buck that are designed with enjoyment in mind (most are used for studio work). JBL LSR305 ($300/pair 2-way actives) may be your best low cost option.
Even something like the AudioEngine A2+ can get your foot in the door ($250/pair, limited bass - perfect for desktop or add a sub, but very small powered speakers with built-in DAC).