I found a really cool organization that works to repair and distribute bikes to refugees in Bielefeld:
It is about 25min from Oerlinghausen by car - do you know anyone that could maybe drive you?
This is the contact info of the organization. Maybe you could ask them if they ever come to Oerlinghausen, and also what the process is to acquire a bike from them. That way, if you have to arrange travel to Bielefeld, you can be sure that there are then bikes for you once you get there :)
Telefon: +49 172 15333333
Let me know if I can help further!!