Plugable's USB dongle is yet another cheap way to add Bluetooth

Plugable USB-C Tablet / Phone / iPad Stand with Docking Station

Plugable USB 2.0 to Ethernet Fast 10/100 LAN Wired Network Adapter Features faster-than-wireless speeds and easy connectivity. The Plugable USB 2.0 to 10/100 Network Adapter adds a Fast Ethernet (RJ45) capable port to any supported system. It uses the ASIX AX88772 chipset for widest possible compatibility.

Plugable USB 2.0 to 10/100 Fast Ethernet LAN Wired Network Adapter

Bluetooth Adapter for PC,Techkey USB Mini Bluetooth 5.0 EDR Dongle for Computer Desktop Wireless Transfer for Laptop Bluetooth Headphones Headset

Plugable USB-C Triple Monitor Docking Station with 3x HDMI Ports

USB Bluetooth with Ubuntu Core

Plugable USB Bluetooth 4.0 Low Energy Micro Adapter

Features a Prolific PL-2303HX Rev D chipset for the best combination of performance and wide driver support. Drivers available for Windows 10, 8.1, 8. 7, Vista, XP, macOS/Mac OS X 10.6 and later; open source drivers included in Linux kernel 2.4.31 and later. Windows 7 - 10 automatically detects and guides driver install without disk. Not compatible with ARM-based Windows (MS Surface).