Landline phone & cable (BT) (Brunswick BN3)

I had a perfectly good phone but BT decided to "upgrade" my service so that the handset no longer works. They are now telling me that there will be a delay in doing the upgrade and that I will need to purchase a new handset to use in the meantime. As a result I am hoping someone can provide me with a BT compatible landline phone & a cable which I can use - I'd be very grateful. Also, if anone has any suggestions of anything I can send to BT to express my heartfelt gratitude to them...