A Low Cost Pleasant Sounding Used CD Player?

 I have the The Marantz Professional PMD-326C it is a well-regarded commercial CD player known for its high-performance features and versatility, particularly in professional settings like retail, education, and hospitality. It supports CD playback, USB thumb drives with MP3 files, and has a 3.5mm AUX input for other audio devices. Key features include front panel lock, power-on play, direct track access, memory of settings after power loss, and balanced XLR outputs. You can get these under $200, I think I paid $100 and like you I only use once in a while and it sounds good to me. The only draw back is there's no power on/off on the remote, You'd have to turn on/off on the unit , or I hooked mine up to a smart plug controlled by Alexa which it works good.

+1 on the Onkyo C-7030...excellent sounding player!

Also, the Rotel RCD-1072 is wonderful.

Oppo used lower model

See if you can find a Parasound.  Their DAC's and CD players always sounded really sweet to me. 

A lot of the CD players will play newer [post 2000] CD's well but not the older ones.  If you are like alot of us here, we have a bunch of old ones we wish would sound better than they do.  One brand that does is Musical Fidelity.  I have two of them now.