Phone handset one piece (Selly Park B5)

Please, I’m in need of a one piece handset phone to connect to the back of my router. I don’t mind the brand or anything like that so long as it’s clean and in good working order. Preferably a short distance for me to travel: Selly park, Kingsheath and their nearest surrounding area. I would consider Solihull if I’m in that vicinity on a particular day. Thank you.