I use a combination of FM radio, SD card player, and speaker, bluetooth+AUX, that mounts with a tripod bolt onto handlebars. There are many options on Amazon and they are of decent quality, waterproof and inexpensive. My specific models are out of stock, but they are all pretty similar, differing in details of the housing and add-ons like horn or light. A couple of examples are below:

https://smile.amazon.com/Waterproof-.../dp/B078J2BZFJ

https://smile.amazon.com/Wireless-Bl.../dp/B07DNV19WV