Hi Humberto,
I'm sorry, I do not have any recommendation but maybe look into dual-mode Bluetooth devices or Classic Bluetooth. I haven't look too much into them except that dual-mode supports Bluetooth LE and Classic Bluetooth devices. I do not know i f they can be small or not or if they are battery operated. The Bluetooth LE devices are able to be small, battery operated, and as the name suggests, low energy. Bluetooth LE also does not support audio for headsets and stereo music or high data rates for file transfers so I am not sure if Bluetooth LE would help in your case. Hope that helps!
BR,
Serena