@WBLskier
I'd highly recommend this unit from Fusion if you're just looking to replace the standard "single-DIN" size factory stereo unit. My family has one in our boat. It's a little pricier than others, but has a great interface and app compatibility that makes running your tunes from your phone even easier than others. From what I understand, it's also got enough juice to power a couple speakers on its own, although an amp always helps things sound better.
https://www.crutchfield.com/p_917RA70I/FUSION-MS-RA70.html?tp=61742
OR this thing if you want something less expensive. It's one of the top sellers on Crutchfield and I have had good experiences with Sony head units.
https://www.crutchfield.com/p_158DSXM55B/Sony-DSX-M55BT.html?tp=61742