That’s a wall mount RV stereo, so your direct replacement options are a bit limited as far as I know but there are some out there. To really make a difference you’ll probably want to reconfigure to add a subwoofer and an amplifier along with the new head unit. That could all get a bit pricey. I might suggest you reach out to Crutchfield, and work with one of their sales reps to see what they recommend, there are so many options to discuss here.
something else to think about is to just buy a high-quality Bluetooth sound bar and control it from your phone, streaming audio from Spotify or other apps, it would probably sound much better then what you have for a reasonable amount of money and you would not need complex or professional installation.
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