1st - $20 - LogitechUltimate Ears WONDERBOOM 3, Small Portable Wireless Bluetooth Speaker, Big Bass 360-Degree Sound for Outdoors, Waterproof (can be submerged in 1 m of water for 30 min), Dustproof IP67, Floatable, 131 ft Range - Performance Blue, 14 hours of audio, Speaker Maximum Output- 10 watts, Frequency response- 80Hz, tap the Outdoor Boost button to get great sound that's specially tuned for outdoor environments, Drop-tested from 5 ft / 1.5 m
https://www.logitech.com/en-us/shop/p/wonderboom-3-bluetooth
2nd - $10 - 2 Speaker and 1 Subwoofer Set
Total output power: 25 watts RMS (50 watts peak) (Subwoofer - 15 watts), 3.5 mm Jack, 2.1 Channel, 5lbs
This 2.1 speaker system delivers balanced acoustics and enhanced bass from a compact subwoofer. With its easy setup, just connect the speakers to the sub-woofer, and plug the sub-woofer into your computer. That's it. System requirement is any device with a headphone jack (3.5 millimeter) input and easily access power and volume on the wired control pod.
https://www.microcenter.com/product/317452/Z313_21_Channel_Computer_Speakers_-_Black?storeID=185
3rd - $5 - This easy-to-use speaker allows you to connect your mobile device via Bluetooth and enjoy your favorite music while on the go. This IPX6-certified waterproof speaker takes any hiking trip head-on. Its compact size along with the included carabiner clip & micro USB charging cable, make it the ideal companion for listening to your favorite tunes while exploring. Bluetooth working range - 33 ft, 2 hours of music at max volume.